question_id stringlengths 8 35 | subject stringclasses 3
values | chapter stringclasses 90
values | topic stringclasses 459
values | question stringlengths 17 24.5k | options stringlengths 2 4.26k | correct_option stringclasses 6
values | answer stringclasses 460
values | explanation stringlengths 1 10.6k | question_type stringclasses 3
values | paper_id stringclasses 154
values | __index_level_0__ int64 2 13.4k |
|---|---|---|---|---|---|---|---|---|---|---|---|
1l6gpudl0 | chemistry | isolation-of-elements | extractions-of-metals | <p>Refining using liquation method is the most suitable for metals with :</p> | [{"identifier": "A", "content": "Low melting point"}, {"identifier": "B", "content": "High boiling point"}, {"identifier": "C", "content": "High electrical conductivity"}, {"identifier": "D", "content": "Less tendency to be soluble in melts than impurities"}] | ["A"] | null | Refining using liquation method is the most suitable
for metals with low melting point | mcq | jee-main-2022-online-26th-july-morning-shift | 2,842 |
1l6i4t5ww | chemistry | isolation-of-elements | extractions-of-metals | <p>The metal that is not extracted from its sulfide ore is :</p> | [{"identifier": "A", "content": "Aluminium"}, {"identifier": "B", "content": "Iron"}, {"identifier": "C", "content": "Lead"}, {"identifier": "D", "content": "Zinc"}] | ["A"] | null | Aluminium is not extracted from sulphide ore. It is
usually extracted from bauxite ore, leaching of
bauxite ore is done followed by electrolytic
reduction. | mcq | jee-main-2022-online-26th-july-evening-shift | 2,843 |
ldo9f3sx | chemistry | isolation-of-elements | extractions-of-metals | Which one of the following statements is incorrect? | [{"identifier": "A", "content": "Cast iron is obtained by melting pig iron with scrap iron and coke using hot air blast."}, {"identifier": "B", "content": "The malleable iron is prepared from cast iron by oxidising impurities in a reverberatory furnace."}, {"identifier": "C", "content": "van Arkel method is used to pur... | ["C"] | null | <p><strong style="color: rgb(230, 0, 0);">Option A</strong>: Cast iron is obtained by melting pig iron (crude iron) with scrap iron and coke (a fuel made from coal) using a hot air blast. The resulting molten metal is poured into molds to form cast iron products.</p><p><strong style="color: rgb(230, 0, 0);">Option B</s... | mcq | jee-main-2023-online-31st-january-evening-shift | 2,844 |
1ldr3x8ky | chemistry | isolation-of-elements | extractions-of-metals | <p>In the extraction of copper, its sulphide ore is heated in a reverberatory furnace after mixing with silica to:</p> | [{"identifier": "A", "content": "remove $$\\mathrm{FeO}$$ as $$\\mathrm{FeSiO}_{3}$$"}, {"identifier": "B", "content": "remove calcium as $$\\mathrm{CaSiO}_{3}$$"}, {"identifier": "C", "content": "decrease the temperature needed for roasting of $$\\mathrm{Cu}_{2} \\mathrm{~S}$$"}, {"identifier": "D", "content": "separa... | ["A"] | null | <p>$$\mathrm{\mathop {FeO}\limits_{Basic} + \mathop {Si{O_2}}\limits_{Acidic} \buildrel {} \over
\longrightarrow \mathop {FeSi{O_3}}\limits_{(Slag)}}$$</p> | mcq | jee-main-2023-online-30th-january-morning-shift | 2,845 |
1lduk6sjw | chemistry | isolation-of-elements | extractions-of-metals | <p>Which one of the following reactions does not occur during extraction of copper?</p> | [{"identifier": "A", "content": "$$\\mathrm{2FeS + 3{O_2} \\to 2FeO + 2S{O_2}}$$"}, {"identifier": "B", "content": "$$\\mathrm{FeO + Si{O_2} \\to FeSi{O_3}}$$"}, {"identifier": "C", "content": "$$\\mathrm{CaO + Si{O_2} \\to CaSi{O_3}}$$"}, {"identifier": "D", "content": "$$\\mathrm{2C{u_2}s + 3{O_2} \\to 2C{u_2}O + 2S{... | ["C"] | null | $$
\begin{aligned}
& \mathrm{CuFeS}_2+\mathrm{O}_2 \stackrel{\text { Partial roasting }}{\longrightarrow} \\\\
& \mathrm{Cu}_2 \mathrm{~S}+\mathrm{FeO}+\mathrm{SO}_2+\underset{\text { very small }}{\mathrm{FeS}}+\underset{\text { very small }}{\mathrm{Cu}_2 \mathrm{O}} \\\\
& \mathrm{Cu}_2 \mathrm{~S}+\mathrm{O}_2 \rig... | mcq | jee-main-2023-online-25th-january-morning-shift | 2,846 |
1ldyfwkvx | chemistry | isolation-of-elements | extractions-of-metals | <p>Match List I with List II</p>
<p><style type="text/css">
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px;
overflow:hidden;padding:10px 5px;word-break:normal;}
.tg th{border-color:black;border-style:solid;bo... | [{"identifier": "A", "content": "A-III, B-IV, C-I, D-II"}, {"identifier": "B", "content": "A-IV, B-II, C-I, D-III"}, {"identifier": "C", "content": "A-I, B-IV, C-II, D-III"}, {"identifier": "D", "content": "A-I, B-III, C-II, D-IV"}] | ["B"] | null | (A) Reverberatory furnance is used for extraction of copper.
<br/><br/>
(B) Electrolytic cell is used for obtaining highly reactive metals like aluminium.
<br/><br/>
(C) Blast furnace is used for pig iron.
<br/><br/>
(D) Zone refining is used for purification of silicon.
| mcq | jee-main-2023-online-24th-january-morning-shift | 2,848 |
1lguz8a9u | chemistry | isolation-of-elements | extractions-of-metals | <p>In the extraction process of copper, the product obtained after carrying out the reactions</p>
<p>(i) $$2 \mathrm{Cu}_{2} \mathrm{~S}+3 \mathrm{O}_{2} \rightarrow 2 \mathrm{Cu}_{2} \mathrm{O}+2 \mathrm{SO}_{2}$$</p>
<p>(ii) $$2 \mathrm{Cu}_{2} \mathrm{O}+\mathrm{Cu}_{2} \mathrm{~S} \rightarrow 6 \mathrm{Cu}+\mathrm{... | [{"identifier": "A", "content": "Copper matte"}, {"identifier": "B", "content": "Blister copper"}, {"identifier": "C", "content": "Reduced copper"}, {"identifier": "D", "content": "Copper scrap"}] | ["B"] | null | The sequence of reactions stated here is part of the copper extraction process, specifically the smelting and conversion stages. Initially, copper sulfide (Cu$_2$S) reacts with oxygen (O$_2$) to form copper(I) oxide (Cu$_2$O) and sulfur dioxide (SO$_2$), according to the equation :
<br/><br/>$$2 \mathrm{Cu}_2 \mathrm{... | mcq | jee-main-2023-online-11th-april-morning-shift | 2,849 |
1lgys775m | chemistry | isolation-of-elements | extractions-of-metals | <p>In Hall - Heroult process, the following is used for reducing $$\mathrm{Al}_{2} \mathrm{O}_{3}$$ :-</p> | [{"identifier": "A", "content": "Magnesium"}, {"identifier": "B", "content": "$$\\mathrm{CaF}_{2}$$"}, {"identifier": "C", "content": "Graphite"}, {"identifier": "D", "content": "$$\\mathrm{Na}_{3} \\mathrm{AlF}_{6}$$"}] | ["C"] | null | <p>In the Hall-Héroult process, graphite anodes are used to reduce alumina (Al₂O₃). During the electrolytic reduction, Al³⁺ ions are reduced at the cathode to form aluminum, while at the anode, oxide ions are oxidized to form oxygen gas. The oxygen gas then reacts with the carbon in the graphite anodes to produce carbo... | mcq | jee-main-2023-online-8th-april-evening-shift | 2,850 |
1lh04k0wi | chemistry | isolation-of-elements | extractions-of-metals | <p>Which of the following metals can be extracted through alkali leaching technique?</p> | [{"identifier": "A", "content": "$$\\mathrm{Sn}$$"}, {"identifier": "B", "content": "Cu"}, {"identifier": "C", "content": "$$\\mathrm{Au}$$"}, {"identifier": "D", "content": "$$\\mathrm{Pb}$$"}] | ["C"] | null | <p>The alkali leaching technique is a method to extract metals from their ores by using an alkaline solution, typically a sodium hydroxide (NaOH) solution, sometimes in the presence of other substances like a cyanide for gold and silver ores. Among the options given, the metal that can be extracted through alkali leach... | mcq | jee-main-2023-online-8th-april-morning-shift | 2,851 |
z9dSEikS79hDzKZwzC99I | chemistry | isolation-of-elements | minerals-and-ores | Match the ores (column A) with the metals (column B) :
<br/><br/><style type="text/css">
.tg {border-collapse:collapse;border-spacing:0;width:100%}
.tg td{font-family:Arial, sans-serif;font-size:14px;padding:10px 5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;border-color:black;}
.tg th{fon... | [{"identifier": "A", "content": "(I)-(c); (II)-(d); (III)-(b); (IV)-(a)"}, {"identifier": "B", "content": "(I)-(a); (II)-(b); (III)-(c); (IV)-(d)"}, {"identifier": "C", "content": "(I)-(b); (II)-(c); (III)-(d); (IV)-(a)"}, {"identifier": "D", "content": "(I)-(c); (II)-(d); (III)-(a); (IV)-(b)"}] | ["A"] | null | Siderite : FeCO<sub>3</sub>
<br><br>Kaolinite : Al<sub>2</sub>(OH)<sub>4</sub>Si<sub>2</sub>O<sub>5</sub>
<br><br>Malachite : CuCO<sub>3</sub>
.Cu(OH)<sub>2</sub>
<br><br>Calamine : ZnCO<sub>3</sub>
<br><br><b>Note : ( Remember all those ores names. Any one of those can be asked in the exam.)</b>
<br><br><b>Oxides Ores... | mcq | jee-main-2019-online-11th-january-morning-slot | 2,852 |
hOg1N4YomLFSwYPHhY20M | chemistry | isolation-of-elements | minerals-and-ores | The ore that contains the metal in the form of
fluoride is : | [{"identifier": "A", "content": "sphalerite"}, {"identifier": "B", "content": "magnetite"}, {"identifier": "C", "content": "malachite"}, {"identifier": "D", "content": "cryolite"}] | ["D"] | null | Magnetite $$ \to $$ Fe<sub>3</sub>O<sub>4</sub>
<br><br>Sphalerite $$ \to $$ ZnS
<br><br>Cryolite $$ \to $$ Na<sub>3</sub>AlF<sub>6</sub>
<br><br>Malachite $$ \to $$ CuCO<sub>3</sub>. Cu(OH)<sub>2</sub> | mcq | jee-main-2019-online-9th-april-morning-slot | 2,853 |
rf9wZRwudY6vHrcF02cFc | chemistry | isolation-of-elements | minerals-and-ores | The one that is not a carbonate ore is : | [{"identifier": "A", "content": "siderite"}, {"identifier": "B", "content": "bauxite"}, {"identifier": "C", "content": "malachite"}, {"identifier": "D", "content": "calamine"}] | ["B"] | null | Bauxite = AlO<sub>x</sub>. (OH)<sub>3–2x</sub>
<br><br>Calamine = ZnCO<sub>3</sub>
<br><br>Siderite = FeCO<sub>3</sub>
<br><br>Malachite = CuCO<sub>3</sub>. Cu(OH)<sub>2</sub> | mcq | jee-main-2019-online-9th-april-evening-slot | 2,854 |
NHVXzELQCCoA5dE6wGWQd | chemistry | isolation-of-elements | minerals-and-ores | The ore that contains both iron and copper is : | [{"identifier": "A", "content": "Copper Pyrites "}, {"identifier": "B", "content": "Malachite "}, {"identifier": "C", "content": "Dolomite "}, {"identifier": "D", "content": "Azurite"}] | ["A"] | null | <table class="tg">
<tbody><tr>
<th class="tg-pjk9">Copper pyrites</th>
<th class="tg-pjk9">:</th>
<th class="tg-pjk9">CuFeS<sub>2</sub></th>
</tr>
<tr>
<td class="tg-pjk9">Malachite</td>
<td class="tg-pjk9">:</td>
<td class="tg-pjk9">CuCO<sub>3</sub> . Cu(OH)<sub>2</sub></td>
</tr>
<tr... | mcq | jee-main-2019-online-9th-january-morning-slot | 2,855 |
oixba3aIu7eJHah4WJjgy2xukft6tb4m | chemistry | isolation-of-elements | minerals-and-ores | The incorrect statement is : | [{"identifier": "A", "content": "bronze is an alloy of copper and tin"}, {"identifier": "B", "content": "cast iron is used to manufacture wrought\niron"}, {"identifier": "C", "content": "german silver is an alloy of zinc, copper\nand nickel"}, {"identifier": "D", "content": "brass is an alloy of copper and nickel"}] | ["D"] | null | Bronze contains 75 – 90% Cu and 10 – 25% Sn
Cast iron is used to make wraugut iron.
<br><br>German silver contains 56% Cu, 24% Zn and
20% Ni.
<br><br>Brass contains 60% Cu and 40% Zn.
<br><br>Note :<br><br><style type="text/css">
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{border-color:black;border-style:s... | mcq | jee-main-2020-online-6th-september-morning-slot | 2,856 |
LfHcemjLzca9VDQAZU1klree9wm | chemistry | isolation-of-elements | minerals-and-ores | The major components in "Gun Metal” are : | [{"identifier": "A", "content": "Al, Cu, Mg and Mn"}, {"identifier": "B", "content": "Cu, Ni and Fe"}, {"identifier": "C", "content": "Cu, Sn and Zn"}, {"identifier": "D", "content": "Cu, Zn and Ni"}] | ["C"] | null | Composition of Gun metal $$ \to $$ 90% Cu + 8% Sn + 2% Zn<br><br>Note :<br><br><style type="text/css">
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px;
overflow:hidden;padding:10px 5px;word-break:normal;}
.tg ... | mcq | jee-main-2021-online-24th-february-morning-slot | 2,857 |
LXfPQaqOoarjlPYReg1klrf28tb | chemistry | isolation-of-elements | minerals-and-ores | Which of the following ore is concentrated using group 1 cyanide salt ? | [{"identifier": "A", "content": "Sphalerite"}, {"identifier": "B", "content": "Malachite"}, {"identifier": "C", "content": "Siderite"}, {"identifier": "D", "content": "Calamine"}] | ["A"] | null | <p>The chemical formulas of given ore in options are as follows</p>
<p>Sphalerite ore : ZnS</p>
<p>Calamine ore : ZnCO<sub>3</sub></p>
<p>Siderite ore : FeCO<sub>3</sub></p>
<p>Malachite ore : Cu(OH)<sub>2</sub>.CuCO<sub>3</sub></p>
<p>Sphalerite ore containing ZnS is concentrated using group is cyanide
salt (NaCN) as ... | mcq | jee-main-2021-online-24th-february-morning-slot | 2,858 |
AN5PkS5wV7BMDC8WZ01klruje7f | chemistry | isolation-of-elements | minerals-and-ores | Math List - I with List - II.<br/><br/><table>
<thead>
<tr>
<th></th>
<th>List I (Metal)</th>
<th></th>
<th>List II (Ores)</th>
</tr>
</thead>
<tbody>
<tr>
<td>(a)</td>
<td>Aluminium</td>
<td>(i)</td>
<td>Siderite</td>
</tr>
<tr>
<td>(b)</td>
<td>Iron</td>
<td>(ii)</td>
<td>Calamine</td>
</tr>
<tr>
<td>(c)</td>
<td>Cop... | [{"identifier": "A", "content": "(a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)"}, {"identifier": "B", "content": "(a)-(i), (b)-(ii), (c)-(iii), (d)-(iv)"}, {"identifier": "C", "content": "(a)-(iii), (b)-(i), (c)-(iv), (d)-(ii)"}, {"identifier": "D", "content": "(a)-(ii), (b)-(iv), (c)-(i), (d)-(iii)"}] | ["C"] | null | Siderite $$ \to $$ FeCO<sub>3</sub>
<br><br>Calamine $$ \to $$ ZnCO<sub>3</sub>
<br><br>Kaolinite $$ \to $$ Si<sub>2</sub>Al<sub>2</sub>O<sub>5</sub>(OH)<sub>4</sub> or Al<sub>2</sub>O<sub>3</sub>.2SiO<sub>2</sub>.2H<sub>2</sub>O
<br><br>Malachite $$ \to $$ CuCO<sub>3</sub>.Cu(OH)<sub>2</sub>
<br><br><b>Note : ( Remem... | mcq | jee-main-2021-online-24th-february-evening-slot | 2,859 |
NtlZbcMBpWbWIcmR3Z1kludhrdn | chemistry | isolation-of-elements | minerals-and-ores | Match List - I with List - II.<br/><br/><table>
<thead>
<tr>
<th></th>
<th>List - I (Ore)</th>
<th></th>
<th>List - II (Element Present)</th>
</tr>
</thead>
<tbody>
<tr>
<td>(a)</td>
<td>Kernite</td>
<td>(i)</td>
<td>Tin</td>
</tr>
<tr>
<td>(b)</td>
<td>Cassiterite</td>
<td>(ii)</td>
<td>Boron</td>
</tr>
<tr>
<td>(c)</... | [{"identifier": "A", "content": "(a) $$ \\to $$ (i), (b) $$ \\to $$ (iii), (c) $$ \\to $$ (iv), (d) $$ \\to $$ (ii)"}, {"identifier": "B", "content": "(a) $$ \\to $$ (iii), (b) $$ \\to $$ (i), (c) $$ \\to $$ (ii), (d) $$ \\to $$ (iv)"}, {"identifier": "C", "content": "(a) $$ \\to $$ (ii), (b) $$ \\to $$ (i), (c) $$ \\t... | ["C"] | null | Kernite : Na<sub>2</sub>B<sub>4</sub>O<sub>7</sub>.4H<sub>2</sub>O (Boron)
<br><br> Cassiterite : SnO<sub>2</sub> (Tin)
<br><br> Calamine : ZnCO<sub>3</sub> (Zinc)
<br><br> Cryolite : Na<sub>3</sub>AlF<sub>6</sub> (Fluorine)
<br><br><b>Note : ( Remember all those ores names. Any one of those can be asked in the exam.)<... | mcq | jee-main-2021-online-26th-february-morning-slot | 2,861 |
Sa6sfv0GfGqEaNmSFw1kluseg2r | chemistry | isolation-of-elements | minerals-and-ores | Match List - I with List - II.<br/><br/><table>
<thead>
<tr>
<th></th>
<th>List - I </th>
<th></th>
<th>List - II</th>
</tr>
</thead>
<tbody>
<tr>
<td>(a)</td>
<td>Siderite</td>
<td>(i)</td>
<td>Cu</td>
</tr>
<tr>
<td>(b)</td>
<td>Calamine</td>
<td>(ii)</td>
<td>Ca</td>
</tr>
<tr>
<td>(c)</td>
<td>Malachite</td>
<td>(i... | [{"identifier": "A", "content": "(a) $$ \\to $$ (i), (b) $$ \\to $$ (ii), (c) $$ \\to $$ (iii), (d) $$ \\to $$ (iv)"}, {"identifier": "B", "content": "(a) $$ \\to $$ (iii), (b) $$ \\to $$ (i), (c) $$ \\to $$ (v), (d) $$ \\to $$ (ii)"}, {"identifier": "C", "content": "(a) $$ \\to $$ (i), (b) $$ \\to $$ (ii), (c) $$ \\to... | ["D"] | null | Siderite $$ \to $$ FeCO<sub>3</sub>
<br><br>Calamine $$ \to $$ ZnCO<sub>3</sub> <br><br>Malachite $$ \to $$ CuCO<sub>3</sub>.Cu(OH)<sub>2</sub> <br><br>Cryolite $$ \to $$ Na<sub>3</sub>AlF<sub>6</sub>
<br><br><b>Note : ( Remember all those ores names. Any one of those can be asked in the exam.)</b>
<br><br><b>Oxides O... | mcq | jee-main-2021-online-26th-february-evening-slot | 2,862 |
1krt5a4n2 | chemistry | isolation-of-elements | minerals-and-ores | Sulphide ion is soft base and its ores are common for metals.<br/><br/>(a) Pb (b) Al (c) Ag (d) Mg | [{"identifier": "A", "content": "(a) and (c) only"}, {"identifier": "B", "content": "(a) and (d) only"}, {"identifier": "C", "content": "(a) and (b) only"}, {"identifier": "D", "content": "(c) and (d) only"}] | ["A"] | null | Pb and Ag commonly exist in the form of sulphide ore like Pbs (galena) and Ag<sub>2</sub>S (Argentite) 'Al' is mainly found in the form of oxide ore whereas 'Mg' is found in the form of halide ore. | mcq | jee-main-2021-online-22th-july-evening-shift | 2,864 |
1ktcqv88a | chemistry | isolation-of-elements | minerals-and-ores | Given below are two statements :<br/><br/>Statement I : Sphalerite is a sulphide or of zinc and copper glance is a sulphide ore of copper.<br/><br/>Statement II : It is possible to separate two sulphide ores by adjusting proportion of oil to water or by using 'depressants' in a forth flotation method.<br/><br/>Choose t... | [{"identifier": "A", "content": "Statement I is true but Statement II is false."}, {"identifier": "B", "content": "Both Statement I and Statement II are true."}, {"identifier": "C", "content": "Statement I is false but Statement II is true."}, {"identifier": "D", "content": "Both Statement I and Statement II are false.... | ["B"] | null | sphalerite-ZnS, copper glance - Cu<sub>2</sub>S two sulphide ores can be separated by adjusting proportions of oil to water or by using 'Depressants'. | mcq | jee-main-2021-online-26th-august-evening-shift | 2,865 |
1ktft0hl2 | chemistry | isolation-of-elements | minerals-and-ores | Match List-I with List-II :<br/><br/><table>
<thead>
<tr>
<th></th>
<th>List - I<br/>(Name of ore/mineral)</th>
<th></th>
<th>List - II<br/>(Chemical formula)</th>
</tr>
</thead>
<tbody>
<tr>
<td>(a)</td>
<td>Calmine</td>
<td>(i)</td>
<td>$$Zns$$</td>
</tr>
<tr>
<td>(b)</td>
<td>Malachite</td>
<td>(ii)</td>
<td>$$FeC{O... | [{"identifier": "A", "content": "(a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)"}, {"identifier": "B", "content": "(a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)"}, {"identifier": "C", "content": "(a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)"}, {"identifier": "D", "content": "(a)-(iii), (b)-(ii), (c)-(iv), (d)-(i)"}] | ["A"] | null | (Name of ore/mineral)<br><br>(a) Calamine - ZnCO<sub>3</sub><br><br>(b) Malachite - CuCO<sub>3</sub> . Cu(OH)<sub>2</sub><br><br>(c) Siderite - FeCO<sub>3</sub><br><br>(d) Sphalerite - ZnS
<br><br><b>Note : ( Remember all those ores names. Any one of those can be asked in the exam.)</b>
<br><br><b>Oxides Ores :</b>
<br... | mcq | jee-main-2021-online-27th-august-evening-shift | 2,866 |
1l54yd40r | chemistry | isolation-of-elements | minerals-and-ores | <p>Match List I with List II.</p>
<p><style type="text/css">
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px;
overflow:hidden;padding:10px 5px;word-break:normal;}
.tg th{border-color:black;border-style:solid;b... | [{"identifier": "A", "content": "A-I, B-II, C-III, D-IV"}, {"identifier": "B", "content": "A-III, B-IV, C-II, D-I"}, {"identifier": "C", "content": "A-IV, B-III, C-I, D-II"}, {"identifier": "D", "content": "A-I, B-II, C-IV, D-III"}] | ["A"] | null | <p>Siderite → FeCO<sub>3</sub></p>
<p>Malachite → CuCO<sub>3</sub>. Cu(OH)<sub>2</sub></p>
<p>Sphalerite → ZnS</p>
<p>Calamine → ZnCO<sub>3</sub></p>
<b>Note : ( Remember all those ores names. Any one of those can be asked in the exam.)</b>
<br><br><b>Oxides Ores :</b>
<br><br> (1) ZnO - Zincite<br><br>(2) Fe<sub>2</su... | mcq | jee-main-2022-online-29th-june-evening-shift | 2,868 |
1l5be15tc | chemistry | isolation-of-elements | minerals-and-ores | <p>(a) Baryte, (b) Galena, (c) Zinc blende and (d) Copper pyrites. How many of these minerals are sulphide based?</p> | [] | null | 3 | Baryte : $ \mathrm{BaSO}_{4}$
<br/><br/>
Galena :$\mathrm{PbS}$
<br/><br/>
Zinc blende: $\mathrm{ZnS}$
<br/><br/>
Copper pyrites : $\mathrm{CuFeS}_{2}$
<br/><br/>
Of the given minerals, only 3 are sulphide based. | integer | jee-main-2022-online-24th-june-evening-shift | 2,869 |
1l6kusclo | chemistry | isolation-of-elements | minerals-and-ores | <p>Among the following ores Bauxite, Siderite, Cuprite, Calamine, Haematite, Kaolinite, Malachite, Magnetite, Sphalerite, Limonite, Cryolite, the number of principal ores if iron is _____________.</p> | [] | null | 4 | The principal ores of iron are :<br/><br/>
Siderite, Haematite, Magnetite, Limonite. | integer | jee-main-2022-online-27th-july-evening-shift | 2,871 |
1ldscw4jc | chemistry | isolation-of-elements | minerals-and-ores | <p>The major component of which of the following ore is sulphide based mineral?</p> | [{"identifier": "A", "content": "Sphalerite"}, {"identifier": "B", "content": "Siderite"}, {"identifier": "C", "content": "Malachite"}, {"identifier": "D", "content": "Calamine"}] | ["A"] | null | <p>Sphalerite $$\to$$ $$\mathrm{ZnS}$$</p>
<p>Calamine $$\to$$ $$\mathrm{ZnCO_3}$$</p>
<p>Malachite $$\to$$ $$\mathrm{CuCO_3.Cu(H)_2}$$</p>
<p>Siderite $$\to$$ $$\mathrm{FeCO_3}$$</p> | mcq | jee-main-2023-online-29th-january-evening-shift | 2,873 |
I47jeIDqs18cVPFh | chemistry | isolation-of-elements | refining-or-purification-of-metal | During the process of electrolytic refining of copper, some metals present as impurity
settle as ‘anode mud’ These are | [{"identifier": "A", "content": "Sn and Ag"}, {"identifier": "B", "content": "Pb and Zn"}, {"identifier": "C", "content": "Ag and Au"}, {"identifier": "D", "content": "Fe and Ni "}] | ["C"] | null | During the process of electrolytic refining Ag and Au are obtained as anode mud. | mcq | aieee-2005 | 2,875 |
mL2j8pBkmkP9cMEn | chemistry | isolation-of-elements | refining-or-purification-of-metal | Which method of purification is represented by the following equation :<br/>
Ti (s) + 2I<sub>2</sub> (g) $$\buildrel {523K} \over
\longrightarrow $$ TiI<sub>4</sub> (g) $$\buildrel {1700K} \over
\longrightarrow $$ Ti (s) + 2I<sub>2</sub> (g) | [{"identifier": "A", "content": "zone refining"}, {"identifier": "B", "content": "cupellation"}, {"identifier": "C", "content": "Poling"}, {"identifier": "D", "content": "Van Arkel"}] | ["D"] | null | Van Arkel is a method in which heat treatment it used to purify metal in this process metals are converted into other metal compound for loosly coupled like as iodine to make metal iodide which are easily decomposed and give pure metal.
<br><br>The process is known as Van Arkel method. | mcq | aieee-2012 | 2,876 |
A2grdNtvtG8yy0iA | chemistry | isolation-of-elements | refining-or-purification-of-metal | In the context of the Hall-Heroult process for the extraction of Al, which of the following statements is
<b>false</b>? | [{"identifier": "A", "content": "Al<sub>2</sub>O<sub>3</sub> is mixed with CaF<sub>2</sub> which lowers the melting point of the mixture and brings conductivity"}, {"identifier": "B", "content": "Al<sup>3+</sup> is reduced at the cathode to form Al"}, {"identifier": "C", "content": "Na<sub>3</sub>AlF<sub>6</sub> serves... | ["C"] | null | In the metallurgy of aluminium purified $$A{l_2}{O_3}$$ is mixed with $$N{a_3}Al{F_6}\,\,$$ $$\,\,\,$$ or $$\,\,\,$$ $$Ca{F_2}$$ which lowers the melting point of the mix and brings conductivity. | mcq | jee-main-2015-offline | 2,877 |
sL3Wqf6NXIKx1ozazaNyl | chemistry | isolation-of-elements | refining-or-purification-of-metal | The electrolytes usually used in the electroplating of gold and silver, respectively are : | [{"identifier": "A", "content": "[Au(CN)<sub>2</sub>]<sup>\u2013</sup> and [Ag(CN)<sub>2</sub>]<sup>\u2013</sup>"}, {"identifier": "B", "content": "[Au(CN)<sub>2</sub>]<sup>\u2013</sup> and [Ag(Cl)<sub>2</sub>]<sup>\u2013</sup>"}, {"identifier": "C", "content": "[Au(OH)<sub>4</sub>]<sup>\u2013</sup> and [Ag(OH)<sub>2... | ["A"] | null | [Au(CN)<sub>2</sub>]<sup>–</sup> and [Ag(CN)<sub>2</sub>]<sup>–</sup> both are soluble complexes.
<br><br>[Au(CN)<sub>2</sub>]<sup>–</sup> ⇌ Au<sup>+</sup> + 2CN<sup>-</sup>
<br><br>[Ag(CN)<sub>2</sub>]<sup>–</sup> ⇌ Ag<sup>+</sup> + 2CN<sup>-</sup>
<br><br>The concentration of produced Au<sup>+</sup> ion and Ag<sup>+<... | mcq | jee-main-2019-online-10th-january-evening-slot | 2,878 |
9AMvJXPku3YEXKskzlQlU | chemistry | isolation-of-elements | refining-or-purification-of-metal | The Mond process is used for the | [{"identifier": "A", "content": "Extraction of Zn"}, {"identifier": "B", "content": "extraction of Mo"}, {"identifier": "C", "content": "Purification of Zr and Ti"}, {"identifier": "D", "content": "Purification of Ni"}] | ["D"] | null | Mond process is used for purification of Ni.
<picture><source media="(max-width: 320px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734265572/exam_images/ulhuvpdf9grix2qgjfve.webp"><img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734267517/exam_images/pwyvekg6egmbotefa4qb.webp" style="max-... | mcq | jee-main-2019-online-8th-april-evening-slot | 2,879 |
hv76feNJffydU1HoTX3rsa0w2w9jwvgw3py | chemistry | isolation-of-elements | refining-or-purification-of-metal | Match the refining methods (Column I) with metals (Column II).
<style type="text/css">
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{font-family:Arial, sans-serif;font-size:14px;padding:10px 5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;border-color:black;}
.tg th{font-family:Aria... | [{"identifier": "A", "content": "(I)-(c) ; (II)-(a) ; (III)-(b) ; (IV)-(d)"}, {"identifier": "B", "content": "(I)-(c) ; (II)-(d) ; (III)-(b) ; (IV)-(a)"}, {"identifier": "C", "content": "(I)-(b) ; (II)-(d) ; (III)-(a) ; (IV)-(c)"}, {"identifier": "D", "content": "(I)-(b) ; (II)-(c) ; (III)-(d) ; (IV)-(a)"}] | ["B"] | null | Liquation is used
for Sn.
<br><br>Zone refining is used for Ga.
<br><br>Van
Arkel method is used for Zr.
<br><br>Mond’s process is used for refining of Ni. | mcq | jee-main-2019-online-10th-april-morning-slot | 2,880 |
zIuBER3XpInZQNVlY23rsa0w2w9jx0u47iw | chemistry | isolation-of-elements | refining-or-purification-of-metal | The correct statement is : | [{"identifier": "A", "content": "zincite is a carbonate ore."}, {"identifier": "B", "content": "Sodium cyanide cannot be used in the metallurgy of silver."}, {"identifier": "C", "content": "aniline is a froth stabilizer."}, {"identifier": "D", "content": "zone refining process is used for the refining of titanium. "}] | ["C"] | null | Zincite is ZnO.
<br><br>Sodium cyanide(AgCN) is used in Macarthur-forest Cyanide Process whre Ag is
leached by dilute solution of NaCN.
<br><br>Aniline is used as froth stabilizer in Froth flotation process.
<br><br>Titanium is refined by Van Arkel method. | mcq | jee-main-2019-online-10th-april-evening-slot | 2,881 |
xTDvUOECR0kp4Jkkhj7k9k2k5epyfz6 | chemistry | isolation-of-elements | refining-or-purification-of-metal | The refining method used when the metal and the impurities have low and high melting temperatures, respectively, is : | [{"identifier": "A", "content": "liquation\n"}, {"identifier": "B", "content": "vapour phase refining "}, {"identifier": "C", "content": "distillation"}, {"identifier": "D", "content": "zone refining "}] | ["A"] | null | Liquation method is used when the melting point
of metal is less compare to the melting point of
the associated impurity. | mcq | jee-main-2020-online-7th-january-evening-slot | 2,882 |
DA3hWpnc9Oe508G6Uljgy2xukg4ma8fm | chemistry | isolation-of-elements | refining-or-purification-of-metal | The element that can be refined by distillation
is : | [{"identifier": "A", "content": "gallium"}, {"identifier": "B", "content": "nickel"}, {"identifier": "C", "content": "zinc"}, {"identifier": "D", "content": "tin"}] | ["C"] | null | Impure zinc is refined by distillation. | mcq | jee-main-2020-online-6th-september-evening-slot | 2,884 |
p2zSlIsnk8VOy8cdoo1kltbbc68 | chemistry | isolation-of-elements | refining-or-purification-of-metal | The method used for the purification of Indium is : | [{"identifier": "A", "content": "zone refining"}, {"identifier": "B", "content": "vapour phase refining"}, {"identifier": "C", "content": "liquation"}, {"identifier": "D", "content": "van Arkel method"}] | ["A"] | null | Zone refining is used for the purification of
indium.
| mcq | jee-main-2021-online-25th-february-evening-slot | 2,885 |
1krq60xrp | chemistry | isolation-of-elements | refining-or-purification-of-metal | The metal that can be purified economically by fractional distillation method is : | [{"identifier": "A", "content": "Fe"}, {"identifier": "B", "content": "Zn"}, {"identifier": "C", "content": "Cu"}, {"identifier": "D", "content": "Ni"}] | ["B"] | null | Zinc can be purified economically by fractional distillation.
Fractional distillation process utilises the boiling point difference
between metal and that of impurity. Using this process, crude zinc
containing Cd, Fe and Pb as impurities can be refined. | mcq | jee-main-2021-online-20th-july-morning-shift | 2,887 |
1ktjym0pa | chemistry | isolation-of-elements | refining-or-purification-of-metal | In the electrolytic refining of blister copper, the total number of main impurities, from the following, removed as anode mud is ______________<br/><br/>Pb, Sb, Se, Te, Ru, Ag, Au and Pt | [] | null | 6 | Anode mud contains Sb, Se, Te, Ag, Au and Pt | integer | jee-main-2021-online-31st-august-evening-shift | 2,889 |
1l57s78ge | chemistry | isolation-of-elements | refining-or-purification-of-metal | <p>Which of the following is structure of a separating funnel?</p> | [{"identifier": "A", "content": "<img src=\"https://app-content.cdn.examgoal.net/fly/@width/image/1l58l9flo/a76aef72-d885-4f5b-a116-b595aa9e92c2/1e1827c0-fc9c-11ec-af50-7b1dc1e93a30/file-1l58l9flp.png?format=png\" data-orsrc=\"https://app-content.cdn.examgoal.net/image/1l58l9flo/a76aef72-d885-4f5b-a116-b595aa9e92c2/1e1... | ["A"] | null | The diagram is option (A) clearly represents separating funnel which is used to separate two immiscible liquids. | mcq | jee-main-2022-online-27th-june-morning-shift | 2,890 |
1l59qs5a3 | chemistry | isolation-of-elements | refining-or-purification-of-metal | <p>Given below are two statements.</p>
<p>Statement I : During electrolytic refining, blister copper deposits precious metals.</p>
<p>Statement II : In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.</p>
<p>In the light of the above statements, choose the correct f... | [{"identifier": "A", "content": "Both Statement I and Statement II are true."}, {"identifier": "B", "content": "Both Statement I and Statement II are false."}, {"identifier": "C", "content": "Statement I is true but Statement II is false."}, {"identifier": "D", "content": "Statement I is false but Statement II is true.... | ["A"] | null | Copper is refined using an electrolytic method.
Anodes are of impure copper and pure copper
strips are taken as cathode.<br/><br/>
Impurities from the blister copper deposit as anode
mud which contains antimony, selenium, tellurium,
silver, gold and platinum.<br/><br/>
Hence both statements are true | mcq | jee-main-2022-online-25th-june-evening-shift | 2,891 |
1l6jkscmu | chemistry | isolation-of-elements | refining-or-purification-of-metal | <p>Which of the following methods are not used to refine any metal?</p>
<p>A. Liquation</p>
<p>B. Calcination</p>
<p>C. Electrolysis</p>
<p>D. Leaching</p>
<p>E. Distillation</p>
<p>Choose the correct answer from the options given below:</p> | [{"identifier": "A", "content": "B and D only"}, {"identifier": "B", "content": "A, B, D and E only"}, {"identifier": "C", "content": "B, D and E only"}, {"identifier": "D", "content": "A, C and E only"}] | ["A"] | null | Leaching and calcination are the processes which are involved in the extraction of the metals.
<br/><br/>
Liquation, Electrolytic refining, Distillation are used in the refining or purification of metal. | mcq | jee-main-2022-online-27th-july-morning-shift | 2,892 |
ldqwflt5 | chemistry | isolation-of-elements | refining-or-purification-of-metal | Given below are two statements:
<br/><br/>
<b>Statement I</b>: During Electrolytic refining, the pure metal is made to act as anode and its impure metallic form is used as cathode.
<br/><br/>
<b>Statement I</b>I: During the Hall-Heroult electrolysis process, purified $\mathrm{Al}_{2} \mathrm{O}_{3}$ is mixed with $\mat... | [{"identifier": "A", "content": "Statement $\\mathrm{I}$ is correct but Statement II is incorrect"}, {"identifier": "B", "content": "Statement I is incorrect but Statement II is correct"}, {"identifier": "C", "content": "Both Statement I and Statement II are incorrect"}, {"identifier": "D", "content": "Both Statement I... | ["B"] | null | <p>During electrolytic refining, the pure metal is made to act as cathode and impure metal used as anode.</p> | mcq | jee-main-2023-online-30th-january-evening-shift | 2,893 |
1lgq433g9 | chemistry | isolation-of-elements | refining-or-purification-of-metal | <p>Which one of the following is most likely a mismatch ?</p> | [{"identifier": "A", "content": "Titanium - van Arkel Method"}, {"identifier": "B", "content": "Zinc - Liquation"}, {"identifier": "C", "content": "Nickel - Mond process"}, {"identifier": "D", "content": "Copper - Electrolysis"}] | ["B"] | null | The most likely mismatch among the given options is : Zinc - Liquation.
<br/><br/>
Liquation is a process of refining metals that involves melting the metal at a temperature slightly below its melting point and allowing it to cool slowly. This causes impurities to separate out as they solidify at different temperatures... | mcq | jee-main-2023-online-13th-april-morning-shift | 2,895 |
pYUtcySZjPJ4w1HX | chemistry | p-block-elements | group-13-elements-(boron-family) | Which one of the following is the correct statement? | [{"identifier": "A", "content": "Boric acid is a protonic acid "}, {"identifier": "B", "content": "Beryllium exhibits coordination number of six "}, {"identifier": "C", "content": "Chlorides of both beryllium and aluminium have bridged chloride structures in solid phase"}, {"identifier": "D", "content": "B<sub>2</sub>H... | ["C"] | null | <img class="question-image" src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734267625/exam_images/jfxbwmxz1ssymbvqlnvr.webp" loading="lazy" alt="AIEEE 2008 Chemistry - p-Block Elements Question 226 English Explanation">
<br><br><b>The coordination number exhibited by beryllium is $$4$$ and not $$6$$ so statem... | mcq | aieee-2008 | 2,897 |
YNKUz0vHr32WvL7ebJTXB | chemistry | p-block-elements | group-13-elements-(boron-family) | The correct statements among I to III regarding
group 13 element oxides are,<br/>
(I) Boron trioxide is acidic.<br/>
(II) Oxides of aluminium and gallium are
amphoteric.<br/>
(III) Oxides of indium and thalliumare basic. | [{"identifier": "A", "content": "(II) and (III) only"}, {"identifier": "B", "content": "(I), (II) and (III)"}, {"identifier": "C", "content": "(I) and (III) only"}, {"identifier": "D", "content": "(I) and (II) only"}] | ["B"] | null | B<sub>2</sub>O<sub>3</sub> is an acidic oxide.
<br><br>Al<sub>2</sub>O<sub>3</sub> and Ga<sub>2</sub>O<sub>3</sub> are amphoteric oxide.
<br><br>In<sub>2</sub>O<sub>3</sub> and Tl<sub>2</sub>O are basic oxide. | mcq | jee-main-2019-online-9th-april-evening-slot | 2,898 |
eHmVE8SCvxX0Dv4LEp7k9k2k5lljc6c | chemistry | p-block-elements | group-13-elements-(boron-family) | The reaction of H<sub>3</sub>N<sub>3</sub>B<sub>3</sub>Cl<sub>3</sub> (A) with LiBH<sub>4</sub> in
tetrahydrofuran gives inorganic benzene (B).
Further, the reaction of (A) with (C) leads to
H<sub>3</sub>N<sub>3</sub>B<sub>3</sub>(Me)<sub>3</sub>. Compounds (B) and (C)
respectively, are : | [{"identifier": "A", "content": "Borazine and MeBr"}, {"identifier": "B", "content": "Diborane and MeMgBr"}, {"identifier": "C", "content": "Boron nitride and MeBr"}, {"identifier": "D", "content": "Borazine and MeMgBr"}] | ["D"] | null | B<sub>3</sub>N<sub>3</sub>H<sub>3</sub>Cl<sub>3</sub>(A) + LiBH<sub>4</sub> $$ \to $$ B<sub>3</sub>N<sub>3</sub>H<sub>6</sub> (B)
<br><br>B = inorganic
benzene or Borazine
<br><br>B<sub>3</sub>N<sub>3</sub>H<sub>3</sub>Cl +
MeMgBr(C) $$ \to $$ B<sub>3</sub>N<sub>3</sub>H<sub>3</sub>(CH<sub>3</sub>)<sub>3</sub> + 3MgBr... | mcq | jee-main-2020-online-9th-january-evening-slot | 2,899 |
QkTgo0X5HYLS0AjoYajgy2xukfou2rt1 | chemistry | p-block-elements | group-13-elements-(boron-family) | Boron and silicon of very high purity can be obtained through : | [{"identifier": "A", "content": "Liquation"}, {"identifier": "B", "content": "Electrolytic refining"}, {"identifier": "C", "content": "Zone refining"}, {"identifier": "D", "content": "Vapour phase refining"}] | ["C"] | null | For boron and silicon zone refining is used. | mcq | jee-main-2020-online-5th-september-evening-slot | 2,900 |
YPcyEMpOikMymQMZSC1klurumfk | chemistry | p-block-elements | group-13-elements-(boron-family) | Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.<br/><br/>Assertion A : In TlI<sub>3</sub>, isomorphous to CsI<sub>3</sub>, the metal is present in +1 oxidation state.<br/><br/>Reason R : Tl metal has fourteen f electrons in its electronic configuration.<br/><br/>In... | [{"identifier": "A", "content": "A is correct but R is not correct"}, {"identifier": "B", "content": "A is not correct but R is correct"}, {"identifier": "C", "content": "Both A and R are correct but R is NOT the correct explanation of A"}, {"identifier": "D", "content": "Both A and R are correct and R is the correct e... | ["C"] | null | A : Due to inert pair effect, Tl is more stable in
+1 oxidation state<br>
Hence TlI<sub>3</sub> and CSI<sub>3</sub> are isomorphous<br><br>
R : Electronic configuration of Tl (81) =
[Xe] 4f<sup>14</sup> 5d<sup>10</sup> 6s<sup>2</sup> 6p<sup>1</sup><br><br>
Both A and R are correct but R is... | mcq | jee-main-2021-online-26th-february-evening-slot | 2,901 |
1l58dn3qk | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>Choose the correct stability order of group 13 elements in their + 1 oxidation state :</p> | [{"identifier": "A", "content": "Al < Ga < In < Tl"}, {"identifier": "B", "content": "Tl < In < Ga < Al"}, {"identifier": "C", "content": "Al < Ga < Tl < In"}, {"identifier": "D", "content": "Al < Tl < Ga < In"}] | ["A"] | null | Due to inert pair effect, stability of +3 oxidation state
decreases and that of +1 oxidation state increases
for (down the group) group 13 elements.<br/><br/>
So, the correct order of stability of group 13
elements in their +1 oxidation state is Al < Ga < In
< Tl. | mcq | jee-main-2022-online-26th-june-morning-shift | 2,902 |
ldo9ndvf | chemistry | p-block-elements | group-13-elements-(boron-family) | Given below are two statements :<br/><br/>
<b>Statement I:</b> Upon heating a borax bead dipped in cupric sulphate in a luminous flame, the colour of the bead becomes green<br/><br/>
<b>Statement II:</b> The green colour observed is due to the formation of copper(I) metaborate<br/><br/>
In light of the above statements... | [{"identifier": "A", "content": "Both Statement I and Statement II are false"}, {"identifier": "B", "content": "Both Statement I and Statement II are true"}, {"identifier": "C", "content": "Statement I is false but Statement II is true"}, {"identifier": "D", "content": "Statement I is true but Statement II is false"}] | ["A"] | null | On treatment with metal salt, boric anhydride
forms metaborate of the metal which gives
different colours in oxidising and reducing flame.
For example, in the case of copper sulphate,
following reactions occur.
<br/><br/>$$
\mathrm{CuSO}_4+\mathrm{B}_2 \mathrm{O}_3 \mathrel{\mathop{\kern0pt\longrightarrow}
\limits_{\le... | mcq | jee-main-2023-online-31st-january-evening-shift | 2,903 |
1ldu1e4ik | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>Potassium dichromate acts as a strong oxidizing agent in acidic solution. During this process, the oxidation state changes from :</p> | [{"identifier": "A", "content": "+ 2 to + 1"}, {"identifier": "B", "content": "+ 6 to + 2"}, {"identifier": "C", "content": "+ 6 to + 3"}, {"identifier": "D", "content": "+ 3 to + 1"}] | ["C"] | null | <p>$\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$ acts as a strong oxidising agent in acidic medium. During this process, oxidation state of $\mathrm{Cr}$ changes from $+6$ to $+3$.</p>
<p>$$
\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{3+}+7 \mathrm{H}_{2} \mathrm{... | mcq | jee-main-2023-online-25th-january-evening-shift | 2,904 |
1lgp2wtkg | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>The covalency and oxidation state respectively of boron in $$\left[\mathrm{BF}_{4}\right]^{-}$$, are :</p> | [{"identifier": "A", "content": "3 and 4"}, {"identifier": "B", "content": "4 and 3"}, {"identifier": "C", "content": "4 and 4"}, {"identifier": "D", "content": "3 and 5"}] | ["B"] | null | In the tetrafluoroborate anion ($$\left[\mathrm{BF}_{4}\right]^{-}$$), boron is bonded to four fluorine atoms through covalent bonds. Therefore, the covalency of boron in this ion is 4.
<br/><br/>
The oxidation state of boron can be calculated by considering the charges on the atoms involved in the anion. Fluorine has ... | mcq | jee-main-2023-online-13th-april-evening-shift | 2,905 |
1lgrk11j3 | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>Given below are two statements :</p>
<p>Statement I : Boron is extremely hard indicating its high lattice energy.</p>
<p>Statement II : Boron has highest melting and boiling point compared to its other group members.</p>
<p>In the light of the above statements, choose the most appropriate answer from the options giv... | [{"identifier": "A", "content": "Both Statement I and Statement II are incorrect"}, {"identifier": "B", "content": "Statement I is incorrect but Statement II is correct"}, {"identifier": "C", "content": "Statement I is correct but Statement II is incorrect"}, {"identifier": "D", "content": "Both statement I and Stateme... | ["D"] | null | <p>Boron is indeed a very hard substance, which does indicate high lattice energy. This is because the lattice energy is a measure of the strength of the forces between the ions in an ionic solid; the greater the lattice energy, the stronger the forces and the harder and more stable the compound. This makes Statement I... | mcq | jee-main-2023-online-12th-april-morning-shift | 2,906 |
1lguzuyn8 | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>For compound having the formula $$\mathrm{GaAlCl}_{4}$$, the correct option from the following is :</p> | [{"identifier": "A", "content": "$$\\mathrm{Cl}$$ forms bond with both $$\\mathrm{Al}$$ and $$\\mathrm{Ga}$$ in $$\\mathrm{GaAlCl}_{4}$$"}, {"identifier": "B", "content": "Oxidation state of $$\\mathrm{Ga}$$ in the salt $$\\mathrm{GaAlCl}_{4}$$ is +3 ."}, {"identifier": "C", "content": "$$\\mathrm{Ga}$$ is coordinated ... | ["D"] | null | <b>Option A :</b> Cl forms bond with both Al and Ga in GaAlCl<sub>4</sub>
<br><br>- This is incorrect. In GaAlCl<sub>4</sub>, chloride ions (Cl<sup>-</sup>) form bonds with Al to create the AlCl<sub>4</sub><sup>-</sup> ion. There is an ionic bond between the Ga<sup>+</sup> cation and the AlCl<sub>4</sub><sup>-</sup> an... | mcq | jee-main-2023-online-11th-april-morning-shift | 2,907 |
jaoe38c1lsc5mr0e | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).</p>
<p>Assertion (A) : Melting point of Boron (2453 K) is unusually high in group 13 elements.</p>
<p>Reason (R) : Solid Boron has very strong crystalline lattice.</p>
<p>In the light of the above statements, c... | [{"identifier": "A", "content": "Both (A) and (R) are correct but (R) Is not the correct explanation of (A)\n"}, {"identifier": "B", "content": "Both (A) and (R) are correct and (R) is the correct explanation of (A)\n"}, {"identifier": "C", "content": "(A) is true but (R) is false\n"}, {"identifier": "D", "content": "(... | ["B"] | null | <p>Solid Boron has very strong crystalline lattice so its melting point unusually high in group 13 elements</p> | mcq | jee-main-2024-online-27th-january-morning-shift | 2,908 |
jaoe38c1lsd8uv19 | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>Given below are two statements:</p>
<p><b>Statement I</b> : Group 13 trivalent halides get easily hydrolyzed by water due to their covalent nature.</p>
<p><b>Statement II</b> : $$\mathrm{AlCl}_3$$ upon hydrolysis in acidified aqueous solution forms octahedral $$\left[\mathrm{Al}\left(\mathrm{H}_2 \mathrm{O}\right)_6... | [{"identifier": "A", "content": "Statement I is false but statement II is true\n"}, {"identifier": "B", "content": "Both statement I and statement II are true\n"}, {"identifier": "C", "content": "Both statement I and statement II are false\n"}, {"identifier": "D", "content": "Statement I is true but statement II is fal... | ["B"] | null | <p>In trivalent state most of the compounds being covalent are hydrolysed in water. Trichlorides on hydrolysis in water form tetrahedral $$\left[\mathrm{M}(\mathrm{OH})_4\right]^{-}$$ species, the hybridisation state of element $$\mathrm{M}$$ is $$\mathrm{sp}^3$$.</p>
<p>In case of aluminium, acidified aqueous solution... | mcq | jee-main-2024-online-31st-january-evening-shift | 2,909 |
lv5grwn0 | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>Give below are two statements: One is labelled as Assertion A and the other is labelled as Reason R:</p>
<p>Assertion A: The stability order of +1 oxidation state of $$\mathrm{Ga}$$, In and $$\mathrm{Tl}$$ is Ga < In < Tl.</p>
<p>Reason R: The inert pair effect stabilizes the lower oxidation state down the gro... | [{"identifier": "A", "content": "A is true but R is false."}, {"identifier": "B", "content": "Both A and R are true but R is NOT the correct explanation of A."}, {"identifier": "C", "content": "A is false but R is true."}, {"identifier": "D", "content": "Both A and R are true and R is the correct explanation of A."}] | ["D"] | null | <p>To evaluate the statements provided, let's first understand the concepts involved:</p>
<p><b>Assertion A:</b> The stability order of the +1 oxidation state of $$\mathrm{Ga}$$, In, and $$\mathrm{Tl}$$ is Ga < In < Tl.</p>
<p><b>Reason R:</b> The inert pair effect stabilizes the lower oxidation state down the ... | mcq | jee-main-2024-online-8th-april-morning-shift | 2,910 |
lv7v3qs2 | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>The number of neutrons present in the more abundant isotope of boron is '$$x$$'. Amorphous boron upon heating with air forms a product, in which the oxidation state of boron is '$$y$$'. The value of $$x+y$$ is _________ .</p> | [{"identifier": "A", "content": "9"}, {"identifier": "B", "content": "6"}, {"identifier": "C", "content": "4"}, {"identifier": "D", "content": "3"}] | ["A"] | null | <p>The most abundant isotope of Boron is $${ }_5 \mathrm{~B}^{11}$$.</p>
<p>No. of neutrons in it $$=x=6$$</p>
<p>$$2 \mathrm{B}(\mathrm{s})+\mathrm{N}_2(\mathrm{g}) \xrightarrow{\Delta} 2 \mathrm{BN}(\mathrm{s})$$</p>
<p>Oxidation state of boron in $$\mathrm{B N=y=+3}$$</p>
<p>So, $$x+y=6+3$$</p>
<p>$$=9$$</p> | mcq | jee-main-2024-online-5th-april-morning-shift | 2,911 |
lv9s2kn9 | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>The correct statements from the following are :</p>
<p>(A) The decreasing order of atomic radii of group 13 elements is $$\mathrm{Tl}>\mathrm{In}>\mathrm{Ga}>\mathrm{Al}>\mathrm{B}$$.</p>
<p>(B) Down the group 13 electronegativity decreases from top to bottom.</p>
<p>(C) $$\mathrm{Al}$$ dissolves in dil.... | [{"identifier": "A", "content": "(A), (B), (C) and (E) only\n"}, {"identifier": "B", "content": "(C) and (E) only\n"}, {"identifier": "C", "content": "(A), (C) and (E) only\n"}, {"identifier": "D", "content": "(A) and (C) only"}] | ["B"] | null | <p>(A) Group-13 size : $$\mathrm{B}<\mathrm{Ga}<\mathrm{Al}<\mathrm{In} \simeq$$ $$\mathrm{TI}$$</p>
<p>(B) In Group-13, Al has exceptional lower EN</p>
<p>$$\mathrm{EN}: \mathrm{B}>\mathrm{TI}>\mathrm{In}>\mathrm{Ga}>\mathrm{Al}$$</p>
<p>$$\begin{aligned}
\text{(C)} \quad & 2 \mathrm{Al}+6 \mathrm{HCl} \rightarrow 2 \... | mcq | jee-main-2024-online-5th-april-evening-shift | 2,912 |
lvc57i3i | chemistry | p-block-elements | group-13-elements-(boron-family) | <p>Given below are two statements :</p>
<p>Statement I : Gallium is used in the manufacturing of thermometers.</p>
<p>Statement II : A thermometer containing gallium is useful for measuring the freezing point $$(256 \mathrm{~K})$$ of brine solution.</p>
<p>In the light of the above statements, choose the correct answer... | [{"identifier": "A", "content": "Both Statement I and Statement II are true\n"}, {"identifier": "B", "content": "Statement I is true but Statement II is false\n"}, {"identifier": "C", "content": "Statement I is false but Statement II is true\n"}, {"identifier": "D", "content": "Both Statement I and Statement II are fal... | ["B"] | null | <p>S-1 is correct as gallium is used in manufacturing of thermometers.</p>
<p>S-2 is incorrect</p> | mcq | jee-main-2024-online-6th-april-morning-shift | 2,913 |
3jVFwhFxVWmQOkdd | chemistry | p-block-elements | group-14-elements-(carbon-family) | The stability of dihalides of $$Si,Ge,Sn$$ and $$Pb$$ increases steadily in the sequence : | [{"identifier": "A", "content": "$$Pb{X_2} < < Sn{X_2} < < Ge{X_2} < < Si{X_2}$$ "}, {"identifier": "B", "content": "$$Ge{X_2} < < Si{X_2} < < Sn{X_2} < < Pb{X_2}$$ "}, {"identifier": "C", "content": "$$Si{X_2} < < Ge{X_2} < < Pb{X_2} < < Sn{X_2}$$ "}, {"id... | ["D"] | null | Reductance of valence shell electrons to participate in bonding is called inert pair effect. The stability of lower oxidation state ($${ + 2\,\,}$$ for group $$14$$ element) increases on going down the group. So the correct order is
<br><br>$$Si{X_2} < Ge{X_2} < Sn{X_2} < Pb{X_2}$$ | mcq | aieee-2007 | 2,915 |
gRS8kXRuqpLanVm0o2AzJ | chemistry | p-block-elements | group-14-elements-(carbon-family) | In graphite and diamond, the percentage of p-characters of the hybrid orbitals in hybridisation are respectively : | [{"identifier": "A", "content": "33 and 25 "}, {"identifier": "B", "content": "33 and 75 "}, {"identifier": "C", "content": "50 and 75"}, {"identifier": "D", "content": "67 and 75 "}] | ["D"] | null | Hybridization of carbon in graphite is sp<sup>2</sup>.
<br><br>So, % of p - in graphite = $${2 \over 3} \times 100$$ = 67%
<br><br>Hybridization of carbon in diamond is sp<sup>3</sup> .
<br><br>So, % of p - in diamond = $${3 \over 4} \times 100$$ = 75% | mcq | jee-main-2018-online-15th-april-morning-slot | 2,916 |
58XuRNVqrRQYyuaWlJMiT | chemistry | p-block-elements | group-14-elements-(carbon-family) | The one that is extensively used as a piezoelectric material is : | [{"identifier": "A", "content": "tridymite"}, {"identifier": "B", "content": "amorphous silica"}, {"identifier": "C", "content": "quartz"}, {"identifier": "D", "content": "mica"}] | ["C"] | null | Those materials which produce electricity under mechanical stress are called piezoelectric material.
<br><br>Quartz is an example of piezoelectric material. | mcq | jee-main-2019-online-9th-january-morning-slot | 2,917 |
7XuuEwZHdouWCRqaWVD5q | chemistry | p-block-elements | group-14-elements-(carbon-family) | The element that does NOT show catenation is : | [{"identifier": "A", "content": "Ge"}, {"identifier": "B", "content": "Si"}, {"identifier": "C", "content": "Sn"}, {"identifier": "D", "content": "Pb"}] | ["D"] | null | <img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264616/exam_images/m2xn7inyuluks8zt13zk.webp" style="max-width: 100%; height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2019 (Online) 12th January Evening Slot Chemistry - p-Block Elements Question 177 English Explanation">
<br>Al... | mcq | jee-main-2019-online-12th-january-evening-slot | 2,918 |
1qEOSDHc3sD3CwppBMeZr | chemistry | p-block-elements | group-14-elements-(carbon-family) | The element that shows greater ability to form p$$\pi $$-p$$\pi $$ multiple bonds, is : | [{"identifier": "A", "content": "Si"}, {"identifier": "B", "content": "Ge"}, {"identifier": "C", "content": "C"}, {"identifier": "D", "content": "Sn"}] | ["C"] | null | <img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734267463/exam_images/dd030x9wxvdop7dwlba0.webp" style="max-width: 100%; height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2019 (Online) 12th January Evening Slot Chemistry - p-Block Elements Question 176 English Explanation">
<br>In... | mcq | jee-main-2019-online-12th-january-evening-slot | 2,919 |
1krusnay7 | chemistry | p-block-elements | group-14-elements-(carbon-family) | Which one of the following compounds of Group-14 elements is not known? | [{"identifier": "A", "content": "[GeCl<sub>6</sub>]<sup>2$$-$$</sup>"}, {"identifier": "B", "content": "[Sn(OH)<sub>6</sub>]<sup>2$$-$$</sup>"}, {"identifier": "C", "content": "[SiCl<sub>6</sub>]<sup>2$$-$$</sup>"}, {"identifier": "D", "content": "[SiF<sub>6</sub>]<sup>2$$-$$</sup>"}] | ["C"] | null | [SiCl<sub>6</sub>]<sup>2$$-$$</sup> does not exist due to steric crowding of surrounding atoms. | mcq | jee-main-2021-online-25th-july-morning-shift | 2,920 |
1l6rjlgq1 | chemistry | p-block-elements | group-14-elements-(carbon-family) | <p>In liquation process used for tin (Sn), the metal :</p> | [{"identifier": "A", "content": "is reacted with acid."}, {"identifier": "B", "content": "is dissolved in water."}, {"identifier": "C", "content": "is brought to molten form which is made to flow on a slope."}, {"identifier": "D", "content": "is fused with NaOH"}] | ["C"] | null | <b>Liquation</b><br/><br/>
In this method a low melting metal like tin can be made to flow on a sloping surface. In this way it is
separated from higher melting impurities | mcq | jee-main-2022-online-29th-july-evening-shift | 2,921 |
1l6rjnx5s | chemistry | p-block-elements | group-14-elements-(carbon-family) | <p>Given below are two statements.</p>
<p>Statement I : Stannane is an example of a molecular hydride.</p>
<p>Statement II : Stannane is a planar molecule.</p>
<p>In the light of the above statement, choose the most appropriate answer from the options given below.</p> | [{"identifier": "A", "content": "Both Statement I and Statement II are true."}, {"identifier": "B", "content": "Both Statement I and Statement II are false."}, {"identifier": "C", "content": "Statement I is true but Statement II is false."}, {"identifier": "D", "content": "Statement I is false but Statement II is true.... | ["C"] | null | Stannane or tin hydride is an inorganic compound with formula $\mathrm{SnH}_{4}$
<br><br><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1l7nq3ot2/881d0bac-2306-4603-8c41-b01b569b993a/3c7ee670-2c87-11ed-a521-1f85f535c206/file-1l7nq3ot3.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/ima... | mcq | jee-main-2022-online-29th-july-evening-shift | 2,922 |
lsao7fl5 | chemistry | p-block-elements | group-14-elements-(carbon-family) | Given below are two statements :
<br/><br/><b>Statement (I) </b>: $\mathrm{SiO}_2$ and $\mathrm{GeO}_2$ are acidic while $\mathrm{SnO}$ and $\mathrm{PbO}$ are amphoteric in nature.
<br/><br/><b>Statement (II)</b> : Allotropic forms of carbon are due to property of catenation and $\mathrm{p} \pi-\mathrm{d} \pi$ bond for... | [{"identifier": "A", "content": "Statement I is false but Statement II is true"}, {"identifier": "B", "content": "Both Statement I and Statement II are false"}, {"identifier": "C", "content": "Both Statement I and Statement II are true"}, {"identifier": "D", "content": "Statement I is true but Statement II is false"}] | ["D"] | null | <p>
Both statements need to be evaluated to determine which (if any) are true:
<br/><br/>
<b>Statement (I)</b> : $\mathrm{SiO}_2$ and $\mathrm{GeO}_2$ are acidic while $\mathrm{SnO}$ and $\mathrm{PbO}$ are amphoteric in nature.
<br/><br/>
This statement is generally true. The oxides of silicon ($\mathrm{SiO}_2$) and ge... | mcq | jee-main-2024-online-1st-february-evening-shift | 2,924 |
jaoe38c1lse739kk | chemistry | p-block-elements | group-14-elements-(carbon-family) | <p>Consider the oxides of group 14 elements
$$\mathrm{SiO}_2, \mathrm{GeO}_2, \mathrm{SnO}_2, \mathrm{PbO}_2, \mathrm{CO}$$ and $$\mathrm{GeO}$$. The amphoteric oxides are</p> | [{"identifier": "A", "content": "$$\\mathrm{SnO}_2, \\mathrm{CO}$$\n"}, {"identifier": "B", "content": "$$\\mathrm{SiO}_2, \\mathrm{GeO}_2$$\n"}, {"identifier": "C", "content": "$$\\mathrm{SnO}_2, \\mathrm{PbO}_2$$\n"}, {"identifier": "D", "content": "$$\\mathrm{GeO}, \\mathrm{GeO}_2$$"}] | ["C"] | null | <p>SnO$$_2$$ and PbO$$_2$$ are amphoteric.</p> | mcq | jee-main-2024-online-31st-january-morning-shift | 2,925 |
lvb2a2db | chemistry | p-block-elements | group-14-elements-(carbon-family) | <p>Evaluate the following statements related to group 14 elements for their correctness.</p>
<p>(A) Covalent radius decreases down the group from $$\mathrm{C}$$ to $$\mathrm{Pb}$$ in a regular manner.</p>
<p>(B) Electronegativity decreases from $$\mathrm{C}$$ to $$\mathrm{Pb}$$ down the group gradually.</p>
<p>(C) Maxi... | [{"identifier": "A", "content": "(A), (B) and (C) Only\n"}, {"identifier": "B", "content": "(A) and (B) Only\n"}, {"identifier": "C", "content": "(C), (D) and (E) Only\n"}, {"identifier": "D", "content": "(C) and (D) Only"}] | ["C"] | null | <p>(A) Covalent radius of group 14 elements increases from $$\mathrm{C}$$ to $$\mathrm{Pb}$$.</p>
<p>(B) Electronegativity decreases from $$\mathrm{C}$$ to $$\mathrm{Si}$$ and thereafter it remains more or less constant.</p>
<p>(C) Maximum covalency of $$\mathrm{C}$$ is 4 as the outermost shell of $$\mathrm{C}$$ is $$2... | mcq | jee-main-2024-online-6th-april-evening-shift | 2,927 |
lvc57i90 | chemistry | p-block-elements | group-14-elements-(carbon-family) | <p>Which of the following material is not a semiconductor.</p> | [{"identifier": "A", "content": "Copper oxide\n"}, {"identifier": "B", "content": "Graphite\n"}, {"identifier": "C", "content": "Silicon\n"}, {"identifier": "D", "content": "Germanium"}] | ["B"] | null | <p>To determine which of the following materials is not a semiconductor, we must understand what a semiconductor is and then look at the properties of each material listed.</p>
<p>Semiconductors are materials that have a conductivity level between conductors (such as metals) and insulators (such as most ceramic materi... | mcq | jee-main-2024-online-6th-april-morning-shift | 2,928 |
MqWmPgL8oGjxUdMh | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | Which of the following statements is true? | [{"identifier": "A", "content": "H<sub>3</sub>PO<sub>3</sub> is a stronger acid than H<sub>2</sub>SO<sub>3</sub>"}, {"identifier": "B", "content": "In aqueous medium HF is a stronger acid than HCl "}, {"identifier": "C", "content": "HClO<sub>4</sub> is a weaker acid than HClO<sub>3</sub>"}, {"identifier": "D", "content... | ["D"] | null | The $$\mathop {HN{O_3}}\limits^{ + 5} $$ is stronger than $$\mathop {HN{O_2}}\limits^{ + 3} .$$ The more the oxidation state of $$N,$$ the more is the acid character. | mcq | aieee-2006 | 2,929 |
jHp4xGIzjwmEpdkG | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | Which of the following statement is wrong? | [{"identifier": "A", "content": "Nitrogen cannot form $$d\\pi - p\\pi$$ bond. "}, {"identifier": "B", "content": "Single N \u2013 N bond is weaker than the single P \u2013 P bond"}, {"identifier": "C", "content": "N<sub>2</sub>O<sub>4</sub> has two resonance structures"}, {"identifier": "D", "content": "The stability o... | ["D"] | null | The case of formation and stability of hydrides decreases rapidly from $$N{H_3}$$ to $$Bi{H_3}.$$. This is evident from their dissociation temperature which decreases from $$N{H_3}$$ to $$B{H_3}.$$ As we go down the group the size of central atom increases and thus metal-hydrogen bond becomes weaker due to decreased ... | mcq | aieee-2011 | 2,930 |
A3mCPKshMHixEWNJ | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | The molecule having smallest bond angle is : | [{"identifier": "A", "content": "NCl<sub>3</sub>"}, {"identifier": "B", "content": "AsCl<sub>3</sub>"}, {"identifier": "C", "content": "SbCl<sub>3</sub>"}, {"identifier": "D", "content": "PCl<sub>3</sub>"}] | ["C"] | null | All the members form volatile halides of the type $$A{X_3}.$$ All halides are pyramidal in shape. The bond angle decreases on moving down the group due to decrease in bond pair-bond pair repulsion.
<br><br>$$\eqalign{
& NC{L_3}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,PC{l_3}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,AsC{l^3} \cr
&am... | mcq | aieee-2012 | 2,931 |
kwY9Syty88M5QITK | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | Which one of the following properties is not shown by NO? | [{"identifier": "A", "content": "It combines with oxygen to form nitrogen dioxide"}, {"identifier": "B", "content": "It\u2019s bond order is 2.5"}, {"identifier": "C", "content": "It is diamagnetic in gaseous state"}, {"identifier": "D", "content": "It is a neutral oxide"}] | ["C"] | null | Nitric oxide is paramagnetic in the gaseous state because of the presence of one unpaired electron in its outermost shell.
<br><br>The electronic configuration of $$NO$$ is
<br><br>$$\sigma _{1s}^2\,\sigma _{1s}^{ * 2}\,\sigma _{2s}^2\,\sigma _{2s}^{ \circ 2}\,\sigma _{{2_{{p_z}}}}^2\,\pi _{{2_{{p_x}}}}^2$$
<br><br>$$... | mcq | jee-main-2014-offline | 2,932 |
QNJhOxqVGyg3czDJWfoj1 | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | A metal ‘M’ reacts with nitrogen gas to afford ‘M<sub>3</sub>N’. ‘M<sub>3</sub>N’ on heating at high temperature gives back ‘M’ and on
reaction with water produces a gas ‘B’. Gas ‘B’ reacts with aqueous
solution of CuSO<sub>4</sub> to form a deep blue compound. ‘M’ and
‘B’ respectively are : | [{"identifier": "A", "content": "Li and NH<sub>3</sub>"}, {"identifier": "B", "content": "Ba and N<sub>2</sub>"}, {"identifier": "C", "content": "Na and NH<sub>3</sub>"}, {"identifier": "D", "content": "Al and N<sub>2</sub>"}] | ["A"] | null | <picture><source media="(max-width: 320px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734266299/exam_images/uzqprmssh9zoqf9yxkwg.webp"><img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264253/exam_images/omgbxgdcuqbdxwzj30bl.webp" style="max-width: 100%;height: auto;display: block;margi... | mcq | jee-main-2017-online-8th-april-morning-slot | 2,933 |
A2m7JRQYhDBKsgWl7L7k9k2k5hlej38 | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | A metal (A) on heating in nitrogen gas gives
compound B. B on treatment with H<sub>2</sub>O gives
a colourless gas which when passed through
CuSO<sub>4</sub> solution gives a dark blue-violet
coloured solution. A and B respectively, are : | [{"identifier": "A", "content": "Na and NaNO<sub>3</sub>"}, {"identifier": "B", "content": "Na and Na<sub>3</sub>N"}, {"identifier": "C", "content": "Mg and Mg<sub>3</sub>N<sub>2</sub>"}, {"identifier": "D", "content": "Mg and Mg(NO<sub>3</sub>)<sub>2</sub>"}] | ["C"] | null | 3Mg(A) + N<sub>2</sub> $$\buildrel \Delta \over
\longrightarrow $$
Mg<sub>3</sub>N<sub>2</sub>(B) $$\buildrel {6{H_2}O} \over
\longrightarrow $$ <br>3Mg(OH)<sub>2</sub> + 2NH<sub>3</sub> (colourless gas)
<br><br>CuSO + 4NH<sub>3</sub> $$ \to $$ [Cu(NH<sub>3</sub>)<sub>4</sub>]SO<sub>4</sub> (deep blue solution) | mcq | jee-main-2020-online-8th-january-evening-slot | 2,935 |
6VwjX0BZ6jok6Cp1MWjgy2xukfte5gjk | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | The correct statement with respect to
dinitrogen is : | [{"identifier": "A", "content": "N<sub>2</sub> is paramagnetic in nature"}, {"identifier": "B", "content": "it can be used as an inert diluent for\nreactive chemicals"}, {"identifier": "C", "content": "it can combine with dioxygen at 25<sup>o</sup>C"}, {"identifier": "D", "content": "liquid dinitrogen is not used in cr... | ["B"] | null | (1) N<sub>2</sub>
is diamagnetic, with no unpaired elctrons.
<br><br>(2) In iron and chemical Industry because of its inertness it is used where an
inert atmosphere is required.
<br><br>(3) N<sub>2</sub>
does not combine with oxygen, hydrogen or most other elements. Nitrogen will combine with
oxygen, however in the p... | mcq | jee-main-2020-online-6th-september-morning-slot | 2,936 |
BINwkByPwnFMgGtH8Q1kluce9ld | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | Find A, B and C in the following reactions :<br/><br/>$$N{H_3} + A + C{O_2} \to {(N{H_4})_2}C{O_3}$$<br/><br/>$${(N{H_4})_2}C{O_3} + {H_2}O + B \to N{H_4}HC{O_3}$$<br/><br/>$$N{H_4}HC{O_3} + NaCl \to N{H_4}Cl + C$$ | [{"identifier": "A", "content": "$$A - {O_2};B - C{O_2};C - N{a_2}C{O_3}$$"}, {"identifier": "B", "content": "$$A - {H_2}O;B - {O_2};C - NaHC{O_3}$$"}, {"identifier": "C", "content": "$$A - {H_2}O;B - {O_2};C - N{a_2}C{O_3}$$"}, {"identifier": "D", "content": "$$A - {H_2}O;B - C{O_2};C - NaHC{O_3}$$"}] | ["D"] | null | <img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734266736/exam_images/mggjaf04sp0vxxt6qobm.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2021 (Online) 26th February Morning Shift Chemistry - p-Block Elements Question 144 English Explanation"> | mcq | jee-main-2021-online-26th-february-morning-slot | 2,937 |
7WCoZ43jUqQDISg2wd1kmht9z0m | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | A group of 15 element, which is a metal and forms a hydride with strongest reducing power among group 15 hydrides. The element is : | [{"identifier": "A", "content": "As"}, {"identifier": "B", "content": "Sb"}, {"identifier": "C", "content": "Bi"}, {"identifier": "D", "content": "P"}] | ["C"] | null | BiH<sub>3</sub> is the strongest reducing agent among the hydrides of 15 group elements as Bi – H bond dissociation energy is very less. | mcq | jee-main-2021-online-16th-march-morning-shift | 2,938 |
1l56aq6vq | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>Nitrogen gas is obtained by thermal decomposition of :</p> | [{"identifier": "A", "content": "Ba(NO<sub>3</sub>)<sub>2</sub>"}, {"identifier": "B", "content": "Ba(N<sub>3</sub>)<sub>2</sub>"}, {"identifier": "C", "content": "NaNO<sub>2</sub>"}, {"identifier": "D", "content": "NaNO<sub>3</sub>"}] | ["B"] | null | $$\mathrm{Ba}\left(\mathrm{N}_{3}\right)_{2} \stackrel{\Delta}{\longrightarrow} \mathrm{Ba}+3 \mathrm{~N}_{2}$$ | mcq | jee-main-2022-online-28th-june-morning-shift | 2,940 |
1l58j1wco | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>The oxide which contains an odd electron at the nitrogen atom is :</p> | [{"identifier": "A", "content": "N<sub>2</sub>O"}, {"identifier": "B", "content": "NO<sub>2</sub>"}, {"identifier": "C", "content": "N<sub>2</sub>O<sub>3</sub>"}, {"identifier": "D", "content": "N<sub>2</sub>O<sub>5</sub>"}] | ["B"] | null | The oxide of nitrogen which contains odd electron
is NO<sub>2</sub><br><br>
<img src="https://app-content.cdn.examgoal.net/fly/@width/image/1l5jttwlg/5649610a-c4ce-407d-8f2c-1e30bd0b2575/3f94f750-02ca-11ed-aa2f-17ed0f361ced/file-1l5jttwlh.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1l5jttwlg/... | mcq | jee-main-2022-online-26th-june-evening-shift | 2,941 |
1l5bda415 | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | PCl<sub>5</sub> is well known, but NCl<sub>5</sub> is not. because, | [{"identifier": "A", "content": "nitrogen is less reactive than phosphorus."}, {"identifier": "B", "content": "nitrogen doesn't have d-orbitals in its valence shell."}, {"identifier": "C", "content": "catenation tendency is weaker in nitrogen than phosphorus."}, {"identifier": "D", "content": "size of phosphorus is lar... | ["B"] | null | $$\mathrm{PCl}_{5}$$ is well known but $$\mathrm{NCl}_{5}$$ is not because nitrogen does not have vacant d-orbitals in its valence shell.<br/><br/> So, nitrogen cannot expand its octet. On the other hand, phosphorus has vacant $$\mathrm{d}$$-orbitals in its valence shell which enables it to expand its octet. | mcq | jee-main-2022-online-24th-june-evening-shift | 2,942 |
1l5w5zzdh | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>A $$\mathrel{\mathop{\kern0pt\longrightarrow}
\limits_{}^{573\,K}} $$ Red phosphorus $$\mathrel{\mathop{\kern0pt\longrightarrow}
\limits_{under\,pressure}^{heat\,;\,803\,K}} $$ B</p>
<p>Red phosphorus is obtained by heating "A" at 573 K, and can be converted to "B" by heating at 803 K under pressure.</p>
<p>A and B,... | [{"identifier": "A", "content": "$$\\beta$$-black phosphorus and white phosphorus."}, {"identifier": "B", "content": "white phosphorus and $$\\beta$$-black phosphorus."}, {"identifier": "C", "content": "$$\\alpha$$-black phosphorus and white phosphorus."}, {"identifier": "D", "content": "white phosphorus and $$\\alpha$... | ["D"] | null | Red phosphrous is obtained by heating white phosphorous at $573 \mathrm{~K}$ in inert atmosphere. When red phosphorous is heated in a sealed tube at $803 \mathrm{~K}$, we get $\alpha$-black phosphorous.
<br/><br/>
$\beta$-Black phosphorous is prepared by heating white phosphorous at $473 \mathrm{~K}$ under high pressur... | mcq | jee-main-2022-online-30th-june-morning-shift | 2,944 |
1lgrl2jd4 | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>Given below are two statements :</p>
<p>Statement I : $$\mathrm{SbCl}_{5}$$ is more covalent than $$\mathrm{SbCl}_{3}$$</p>
<p>Statement II: The higher oxides of halogens also tend to be more stable than the lower ones.</p>
<p>In the light of the above statements, choose the most appropriate answer from the options ... | [{"identifier": "A", "content": "Both statement I and Statement II are correct"}, {"identifier": "B", "content": "Both Statement I and Statement II are incorrect"}, {"identifier": "C", "content": "Statement I is correct but Statement II is incorrect"}, {"identifier": "D", "content": "Statement I is incorrect but Statem... | ["A"] | null | <p>Statement I : SbCl₅ is more covalent than SbCl₃</p>
<p>In general, the covalent character of a compound is directly proportional to the polarization, and the polarization depends upon the size of the cation and the charge on the cation. If the charge on the cation increases or if the size of the cation decreases, th... | mcq | jee-main-2023-online-12th-april-morning-shift | 2,947 |
lsbmy2l2 | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | The number of white coloured salts, among the following is<br/><br/>
(a) $\mathrm{SrSO}_4$<br/><br/>
(b) $\mathrm{Mg}\left(\mathrm{NH}_4\right) \mathrm{PO}_4$<br/><br/>
(c) $\mathrm{BaCrO}_4$<br/><br/>
(d) $\mathrm{Mn}(\mathrm{OH})_2$<br/><br/>
(e) $\mathrm{PbSO}_4$<br/><br/>
(f) $\mathrm{PbCrO}_4$<br/><br/>
(g) $\math... | [] | null | 5 | <p>To determine the number of white coloured salts among the listed compounds, we look at their common color characteristics:</p><p>(a) $\mathrm{SrSO}_4$ - Generally, most sulfate salts are white unless the cation imparts a color. Strontium sulfate is indeed white.</p><p>(b) $\mathrm{Mg}\left(\mathrm{NH}_4\right)\mathr... | integer | jee-main-2024-online-1st-february-morning-shift | 2,949 |
jaoe38c1lsfmftc2 | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>On passing a gas, '$$\mathrm{X}$$', through Nessler's regent, a brown precipitate is obtained. The gas '$$\mathrm{X}$$' is</p> | [{"identifier": "A", "content": "$$\\mathrm{Cl}_2$$\n"}, {"identifier": "B", "content": "$$\\mathrm{CO}_2$$\n"}, {"identifier": "C", "content": "$$\\mathrm{NH}_3$$\n"}, {"identifier": "D", "content": "$$\\mathrm{H}_2 \\mathrm{S}$$"}] | ["C"] | null | <p>Nessler's Reagent Reaction :</p>
<p>$$\underset{\text { (Nessler's Reagent) }}{2 \mathrm{~K}_2 \mathrm{HgI}_4}+\mathrm{NH}_3+3 \mathrm{KOH} \rightarrow \underset{\substack{\text { (lodine of Millon's base } \\ \text { (Brown precipitate }}}{\mathrm{HgO} . \mathrm{Hg}\left(\mathrm{NH}_2\right) \mathrm{I}}+7 \mathrm{K... | mcq | jee-main-2024-online-29th-january-evening-shift | 2,950 |
1lsg7qzxc | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>Choose the correct statements about the hydrides of group 15 elements.</p>
<p>A. The stability of the hydrides decreases in the order $$\mathrm{NH}_3>\mathrm{PH}_3>\mathrm{AsH}_3> \mathrm{SbH}_3>\mathrm{BiH}_3$$.</p>
<p>B. The reducing ability of the hydride increases in the order $$\mathrm{NH}_3<\mat... | [{"identifier": "A", "content": "C and D only"}, {"identifier": "B", "content": "A and D only"}, {"identifier": "C", "content": "A and B only"}, {"identifier": "D", "content": "B and C only"}] | ["C"] | null | <p>On moving down the group, bond strength of $$\mathrm{M}-\mathrm{H}$$ bond decreases, which reduces the thermal stability but increases reducing nature of hydrides, hence A and B are correct statements.</p> | mcq | jee-main-2024-online-30th-january-evening-shift | 2,951 |
lv40va43 | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>Identify the incorrect statements about group 15 elements :</p>
<p>(A) Dinitrogen is a diatomic gas which acts like an inert gas at room temperature.</p>
<p>(B) The common oxidation states of these elements are $$-3,+3$$ and +5.</p>
<p>(C) Nitrogen has unique ability to form $$\mathrm{p} \pi-\mathrm{p} \pi$$ multipl... | [{"identifier": "A", "content": "(A), (C), (E) only\n"}, {"identifier": "B", "content": "(D) and (E) only\n"}, {"identifier": "C", "content": "(A), (B), (D) only\n"}, {"identifier": "D", "content": "(B), (D), (E) only"}] | ["B"] | null | <p>Let's analyze each statement step by step to identify the incorrect ones:</p>
<p>(A) Dinitrogen is a diatomic gas which acts like an inert gas at room temperature.</p>
<p>This statement is generally correct. Dinitrogen ($$N_2$$) is indeed a diatomic gas and is very inert at room temperature due to the strong tripl... | mcq | jee-main-2024-online-8th-april-evening-shift | 2,952 |
lv40v8yq | chemistry | p-block-elements | group-15-elements-(nitrogen-family) | <p>In qualitative test for identification of presence of phosphorous, the compound is heated with an oxidising agent. Which is further treated with nitric acid and ammonium molybdate respectively. The yellow coloured precipitate obtained is :</p> | [{"identifier": "A", "content": "$$\\mathrm{Na}_3 \\mathrm{PO}_4 \\cdot 12 \\mathrm{MoO}_3$$\n"}, {"identifier": "B", "content": "$$\\left(\\mathrm{NH}_4\\right)_3 \\mathrm{PO}_4 \\cdot 12\\left(\\mathrm{NH}_4\\right)_2 \\mathrm{MoO}_4$$\n"}, {"identifier": "C", "content": "$$\\mathrm{MoPO}_4 \\cdot 21 \\mathrm{NH}_4 \... | ["D"] | null | <p>For test of phosphorus:</p>
<p>$$\mathrm{{H_3}P{O_4} + 12{(N{H_4})_2}Mo{O_4} + 21HN{O_3} \to \mathop {{{(N{H_4})}_3}\,.\,12Mo{O_3}}\limits_{(Yellow\,ppt)} + 21N{H_4}N{O_3} + 12{H_2}O}$$</p> | mcq | jee-main-2024-online-8th-april-evening-shift | 2,953 |
9LasynDnRjTSq5LU | chemistry | p-block-elements | group-16-elements-(oxygen-family) | Which one of the following substances has the highest proton affinity? | [{"identifier": "A", "content": "H<sub>2</sub>S"}, {"identifier": "B", "content": "NH<sub>3</sub>"}, {"identifier": "C", "content": "PH<sub>3</sub>"}, {"identifier": "D", "content": "H<sub>2</sub>O"}] | ["B"] | null | Among the given compounds, the $$N{H_3}$$ is most basic. Hence has highest proton affinity. | mcq | aieee-2003 | 2,954 |
RlatqLtie51tfsoJ | chemistry | p-block-elements | group-16-elements-(oxygen-family) | Regular use of which of the following fertilizer increases the acidity of soil? | [{"identifier": "A", "content": "Potassium nitrate"}, {"identifier": "B", "content": "Urea "}, {"identifier": "C", "content": "Superphosphate of lime"}, {"identifier": "D", "content": "Ammonium sulphate "}] | ["D"] | null | $$\,{\left( {N{H_4}} \right)_2}S{O_4} + 2{H_2}O\buildrel \, \over
\longrightarrow 2{H_2}S{O_4} + N{H_4}OH$$
<br><br>$${H_2}S{O_4}\,\,$$ is strong acid and increases the acidity of soil. | mcq | aieee-2007 | 2,955 |
mkBnXGogUTYq8ycE | chemistry | p-block-elements | group-16-elements-(oxygen-family) | Which of the following statements regarding sulphur is incorrect? | [{"identifier": "A", "content": "The vapour at 200<sup>o</sup>C consists mostly of S<sub>8</sub> rings "}, {"identifier": "B", "content": "At 600<sup>o</sup>C the gas mainly consists of S<sub>2</sub> molecules "}, {"identifier": "C", "content": "The oxidation state of sulphur is never less than +4 in its compounds "}, ... | ["C"] | null | Oxidation of sulphur varies from $$-2$$ to $$+6$$ in its various compounds. | mcq | aieee-2011 | 2,956 |
Fkyt13wViFAxUzyK | chemistry | p-block-elements | group-16-elements-(oxygen-family) | <b>Assertion :</b> Nitrogen and Oxygen are the main components in the atmosphere but these do not react to
form oxides of nitrogen.<br/><br>
<b>Reason :</b> The reaction between nitrogen and oxygen requires high temperature. </br> | [{"identifier": "A", "content": "Both assertion and reason are correct, and the reason is the correct explanation for the assertion"}, {"identifier": "B", "content": "Both assertion and reason are correct, but the reason is not the correct explanation for the assertion"}, {"identifier": "C", "content": "The assertion i... | ["A"] | null | Nitrogen and oxygen in air do not react to form oxides of nitrogen in atmosphere because the reaction between nitrogen and oxygen requires high temperature. | mcq | jee-main-2015-offline | 2,957 |
9ZQnqqsiVsaZaU7IWc1klrh6xzl | chemistry | p-block-elements | group-16-elements-(oxygen-family) | The reaction of sulphur in alkaline medium is given below:<br/><br/>
<img src="data:image/png;base64,UklGRvwIAABXRUJQVlA4IPAIAADQMwCdASrFAS8APm0wlUakIyIhKHb74IANiWkOrC9V+YHEVgWMz4d/i3aR/Wvxx8Rvzv96/nP7T+lbWh5pPp995/nH7g/2P1o/rvgDwAvVH97/mX4xelz9IO4Kp1+onsBeyvx3/MfzP91f8X53P8d/H/3A9wPpb/XvcA/ln88/1f829jv7d4LXen6gfAJ/Nv5... | [] | null | 12 | The two half reaction, one separately are as follows<br/><br/>$${S_8} + 16{e^ - }\buildrel {} \over
\longrightarrow 8{S^{2 - }}$$ (Reduction)<br/><br/>$${S_8} + 12{H_2}O\buildrel {} \over
\longrightarrow 4{S_2}O_3^{2 - } + 24{H^ + } + 16{e^ - }$$
<br/>_____________________________________
<br/><br/>$$2{S_8} + 12{H_2}... | integer | jee-main-2021-online-24th-february-morning-slot | 2,959 |
e0DGPaqfKBSF9y7rmD1kmln75qn | chemistry | p-block-elements | group-16-elements-(oxygen-family) | Match List - I with List - II<br/><br/><table>
<thead>
<tr>
<th></th>
<th>List - I<br/>(process)</th>
<th></th>
<th>List - II<br/>(catalyst)</th>
</tr>
</thead>
<tbody>
<tr>
<td>(a)</td>
<td>Deacron's process</td>
<td>(i)</td>
<td>ZSM-5</td>
</tr>
<tr>
<td>(b)</td>
<td>Contact process</td>
<td>(ii)</td>
<td>$$CuC{l_2}$... | [{"identifier": "A", "content": "(a)-(ii), (b)-(iv), (c)-(i), (d)-(iii)"}, {"identifier": "B", "content": "(a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)"}, {"identifier": "C", "content": "(a)-(iii), (b)-(i), (c)-(iv), (d)-(ii)"}, {"identifier": "D", "content": "(a)-(iv), (b)-(ii), (c)-(i), (d)-(iii)"}] | ["A"] | null | In manufacture of H<sub>2</sub>SO<sub>4</sub> (contact process), V<sub>2</sub>O<sub>5</sub> is used as a catalyst.<br><br>
Ni catalysts enables the hydrogenation of fats.
CuCl<sub>2</sub> is used as catalyst in Deacon's process.
ZSM-5 used as catalyst in cracking of
hydrocarbons. | mcq | jee-main-2021-online-18th-march-morning-shift | 2,960 |
1ktecrru0 | chemistry | p-block-elements | group-16-elements-(oxygen-family) | In polythionic acid, H<sub>2</sub>S<sub>x</sub>O<sub>6</sub> (x = 3 to 5) the oxidation state(s) of sulphur is/are : | [{"identifier": "A", "content": "+ 5 only"}, {"identifier": "B", "content": "+ 6 only"}, {"identifier": "C", "content": "+ 3 and + 5 only"}, {"identifier": "D", "content": "0 and + 5 only"}] | ["D"] | null | <img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734267357/exam_images/jdwqccw4nfw8iobfohz4.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2021 (Online) 27th August Morning Shift Chemistry - p-Block Elements Question 120 English Explanation"> | mcq | jee-main-2021-online-27th-august-morning-shift | 2,963 |
1l54yldjx | chemistry | p-block-elements | group-16-elements-(oxygen-family) | <p>Sulphur dioxide is one of the components of polluted air. SO<sub>2</sub> is also a major contributor to acid rain. The correct and complete reaction to represent acid rain caused by SO<sub>2</sub> is :</p> | [{"identifier": "A", "content": "2SO<sub>2</sub> + O<sub>2</sub> $$\\to$$ 2SO<sub>3</sub>"}, {"identifier": "B", "content": "SO<sub>2</sub> + O<sub>3</sub> $$\\to$$ SO<sub>3</sub> + O<sub>2</sub>"}, {"identifier": "C", "content": "SO<sub>2</sub> + H<sub>2</sub>O<sub>2</sub> $$\\to$$ H<sub>2</sub>SO<sub>4</sub>"}, {"ide... | ["D"] | null | <p>$$2\text{SO}_{2} +\text{O}_{2} +\text{2H}_{2} \text{O} \longrightarrow \text{2H}_{2} \text{SO}_{4} $$</p>
<p>Acid rain occurs due to increased concentration of
oxides of sulphur and Nitrogen.</p> | mcq | jee-main-2022-online-29th-june-evening-shift | 2,964 |
1l56yklkt | chemistry | p-block-elements | group-16-elements-(oxygen-family) | <p>Match List I with List II.</p>
<p><style type="text/css">
.tg {border-collapse:collapse;border-spacing:0;}
.tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px;
overflow:hidden;padding:10px 5px;word-break:normal;}
.tg th{border-color:black;border-style:solid;b... | [{"identifier": "A", "content": "A-III, B-I, C-II, D-IV"}, {"identifier": "B", "content": "A-II, B-I, C-IV, D-III"}, {"identifier": "C", "content": "A-IV, B-I, C-III, D-II"}, {"identifier": "D", "content": "A-IV, B-I, C-II, D-III"}] | ["D"] | null | $\mathrm{CO}_{3}^{2-}$ : On action of dil sulphuric acid, $\mathrm{CO}_{2}$ gas is released which turns lime water milky.
<br/><br/>
$\mathrm{S}^{2-} $ : On action of dil sulphuric acid, $\mathrm{H}_{2} \mathrm{~S}$ gas is released which turns lead acetate paper black.
<br/><br/>
$\mathrm{SO}_{3}^{2-}$ : On action of d... | mcq | jee-main-2022-online-27th-june-evening-shift | 2,965 |
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