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572b4ab5111d821400f38e26
Zinc
Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given ...
We have evidence of zinc production dating back to the 6th century thanks to what mine?
{ "text": [ "Rajasthan" ], "answer_start": [ 299 ] }
572b4ab5111d821400f38e27
Zinc
Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given ...
What early process was used to make zinc?
{ "text": [ "distillation process" ], "answer_start": [ 503 ] }
572b4ab5111d821400f38e28
Zinc
Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given ...
What were the names given to zinc by early alchemists?
{ "text": [ "\"philosopher's wool\" or \"white snow\"" ], "answer_start": [ 611 ] }
57296f966aef051400154ea2
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
Who named the element zinc?
{ "text": [ "Paracelsus" ], "answer_start": [ 48 ] }
57296f966aef051400154ea3
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
What was zinc named after?
{ "text": [ "Zinke" ], "answer_start": [ 81 ] }
57296f966aef051400154ea4
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
Who is credited with discovering zinc?
{ "text": [ "Andreas Sigismund Marggraf" ], "answer_start": [ 118 ] }
57296f966aef051400154ea5
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
What two people discovered the electrochemical properties of zinc?
{ "text": [ "Luigi Galvani and Alessandro Volta" ], "answer_start": [ 210 ] }
57296f966aef051400154ea6
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
Where can you find zinc chloride?
{ "text": [ "deodorants" ], "answer_start": [ 629 ] }
572b4ba5f75d5e190021fd6a
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
Who is credited as giving zinc its name?
{ "text": [ "Paracelsus" ], "answer_start": [ 48 ] }
572b4ba5f75d5e190021fd6b
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
What does the name zinc or zinke mean?
{ "text": [ "(prong, tooth)" ], "answer_start": [ 87 ] }
572b4ba5f75d5e190021fd6c
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
Who discovered pure metallic zinc?
{ "text": [ "Andreas Sigismund Marggraf" ], "answer_start": [ 118 ] }
572b4ba5f75d5e190021fd6d
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
What is the most common use for zinc?
{ "text": [ "(hot-dip galvanizing" ], "answer_start": [ 344 ] }
572b4ba5f75d5e190021fd6e
Zinc
The element was probably named by the alchemist Paracelsus after the German word Zinke (prong, tooth). German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resista...
What is a common use for zinc chloride?
{ "text": [ "deodorants" ], "answer_start": [ 629 ] }
5729701b1d04691400779453
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
How many people are affected by zinc deficiency?
{ "text": [ "two billion" ], "answer_start": [ 211 ] }
5729701b1d04691400779454
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
What can consumption of excess zinc cause?
{ "text": [ "ataxia, lethargy and copper deficiency" ], "answer_start": [ 559 ] }
5729701b1d04691400779455
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
Where can you find enzymes with a zinc atom in the reactive center?
{ "text": [ "biochemistry," ], "answer_start": [ 467 ] }
5729701b1d04691400779456
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
What can a lack of zinc cause in children?
{ "text": [ "growth retardation, delayed sexual maturation, infection susceptibility, and diarrhea" ], "answer_start": [ 314 ] }
572b4ce0f75d5e190021fd7c
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
What is extremely important to prenatal and postnatal development?
{ "text": [ "Zinc" ], "answer_start": [ 0 ] }
572b4ce0f75d5e190021fd7d
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
What can cause symptoms in children ranging from diarrhea to retarded growth?
{ "text": [ "Zinc deficiency" ], "answer_start": [ 181 ] }
572b4ce0f75d5e190021fd7e
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
In what substance can you find a zinc atom within its reactive center?
{ "text": [ "alcohol dehydrogenase" ], "answer_start": [ 489 ] }
572b4ce0f75d5e190021fd7f
Zinc
Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth...
What causes symptoms such as lethargy and copper deficiency?
{ "text": [ "excess zinc" ], "answer_start": [ 537 ] }
572970803f37b319004783c5
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
What color is zinc?
{ "text": [ "bluish-white" ], "answer_start": [ 10 ] }
572970803f37b319004783c6
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
Is iron more dense than zinc?
{ "text": [ "It is somewhat less dense than iron" ], "answer_start": [ 123 ] }
572970803f37b319004783c7
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
At what temperature does the metal become malleable?
{ "text": [ "100 and 150 °C" ], "answer_start": [ 455 ] }
572970803f37b319004783c8
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
At what temperature to zinc become brittle?
{ "text": [ "210 °C" ], "answer_start": [ 477 ] }
572970803f37b319004783c9
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
What is the boiling point of zinc?
{ "text": [ "907 °C" ], "answer_start": [ 668 ] }
572b4db9111d821400f38e3e
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
In it's pre commercial state, what color is zinc?
{ "text": [ "bluish-white" ], "answer_start": [ 10 ] }
572b4db9111d821400f38e3f
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
What is the crystalline structure of sync?
{ "text": [ "hexagonal" ], "answer_start": [ 169 ] }
572b4db9111d821400f38e40
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
What happens to zinc when it is manipulated to the temperatures between 100 and 150 Celsius?
{ "text": [ "becomes malleable" ], "answer_start": [ 429 ] }
572b4db9111d821400f38e41
Zinc
Zinc is a bluish-white, lustrous, diamagnetic metal, though most common commercial grades of the metal have a dull finish. It is somewhat less dense than iron and has a hexagonal crystal structure, with a distorted form of hexagonal close packing, in which each atom has six nearest neighbors (at 265.9 pm) in its own pl...
At what temperature can zinc be pulverized?
{ "text": [ "210 °C" ], "answer_start": [ 477 ] }
5729710a6aef051400154ece
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
How many radioisotopes of zinc have been discovered?
{ "text": [ "Several dozen" ], "answer_start": [ 0 ] }
5729710a6aef051400154ecf
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
What is the longest half life of the isotopes?
{ "text": [ "243.66" ], "answer_start": [ 84 ] }
5729710a6aef051400154ed0
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
What does the superscript m represent?
{ "text": [ "metastable isotope" ], "answer_start": [ 284 ] }
5729710a6aef051400154ed1
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
How many excited states does 61Zn have?
{ "text": [ "three" ], "answer_start": [ 457 ] }
5729710a6aef051400154ed2
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
How many excited states does 73Zn have?
{ "text": [ "two" ], "answer_start": [ 491 ] }
572b5109111d821400f38e5a
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
What is the most long lived radio isotope?
{ "text": [ "65Zn" ], "answer_start": [ 53 ] }
572b5109111d821400f38e5b
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
What is the half life of 72Zn?
{ "text": [ "46.5 hours" ], "answer_start": [ 171 ] }
572b5109111d821400f38e5c
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
How many nuclear isomers does zinc have?
{ "text": [ "10" ], "answer_start": [ 192 ] }
572b5109111d821400f38e5d
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
What does the superscript "m" indicate?
{ "text": [ "metastable isotope" ], "answer_start": [ 284 ] }
572b5109111d821400f38e5e
Zinc
Several dozen radioisotopes have been characterized. 65Zn, which has a half-life of 243.66 days, is the most long-lived radioisotope, followed by 72Zn with a half-life of 46.5 hours. Zinc has 10 nuclear isomers. 69mZn has the longest half-life, 13.76 h. The superscript m indicates a metastable isotope. The nucleus of a...
What does a metastable isotope do to return to ground state from an excited state?
{ "text": [ "emitting a photon in the form of a gamma ray" ], "answer_start": [ 402 ] }
5729717d6aef051400154ed8
Zinc
The chemistry of zinc is dominated by the +2 oxidation state. When compounds in this oxidation state are formed the outer shell s electrons are lost, which yields a bare zinc ion with the electronic configuration [Ar]3d10. In aqueous solution an octahedral complex, [Zn(H 2O)6]2+ is the predominant species. The volatili...
What oxidation state dominates zinc?
{ "text": [ "+2" ], "answer_start": [ 42 ] }
5729717d6aef051400154eda
Zinc
The chemistry of zinc is dominated by the +2 oxidation state. When compounds in this oxidation state are formed the outer shell s electrons are lost, which yields a bare zinc ion with the electronic configuration [Ar]3d10. In aqueous solution an octahedral complex, [Zn(H 2O)6]2+ is the predominant species. The volatili...
what are the only two oxidation states known for zinc?
{ "text": [ "+1 or +2" ], "answer_start": [ 530 ] }
572b520df75d5e190021fd84
Zinc
The chemistry of zinc is dominated by the +2 oxidation state. When compounds in this oxidation state are formed the outer shell s electrons are lost, which yields a bare zinc ion with the electronic configuration [Ar]3d10. In aqueous solution an octahedral complex, [Zn(H 2O)6]2+ is the predominant species. The volatili...
What oxidation state dominates the chemistry of zinc?
{ "text": [ "+2" ], "answer_start": [ 42 ] }
572b520df75d5e190021fd87
Zinc
The chemistry of zinc is dominated by the +2 oxidation state. When compounds in this oxidation state are formed the outer shell s electrons are lost, which yields a bare zinc ion with the electronic configuration [Ar]3d10. In aqueous solution an octahedral complex, [Zn(H 2O)6]2+ is the predominant species. The volatili...
What are the only two oxidation states known for zinc compounds?
{ "text": [ "+1 or +2" ], "answer_start": [ 530 ] }
572b5334111d821400f38e64
Zinc
Zinc chemistry is similar to the chemistry of the late first-row transition metals nickel and copper, though it has a filled d-shell, so its compounds are diamagnetic and mostly colorless. The ionic radii of zinc and magnesium happen to be nearly identical. Because of this some of their salts have the same crystal stru...
Because zinc has a filled d-shell, its compounds are usually what?
{ "text": [ "diamagnetic and mostly colorless." ], "answer_start": [ 155 ] }
572b5334111d821400f38e65
Zinc
Zinc chemistry is similar to the chemistry of the late first-row transition metals nickel and copper, though it has a filled d-shell, so its compounds are diamagnetic and mostly colorless. The ionic radii of zinc and magnesium happen to be nearly identical. Because of this some of their salts have the same crystal stru...
The ionic radii of what two elements are almost identical?
{ "text": [ "zinc and magnesium" ], "answer_start": [ 208 ] }
572b5334111d821400f38e66
Zinc
Zinc chemistry is similar to the chemistry of the late first-row transition metals nickel and copper, though it has a filled d-shell, so its compounds are diamagnetic and mostly colorless. The ionic radii of zinc and magnesium happen to be nearly identical. Because of this some of their salts have the same crystal stru...
What is the determining factor where zinc and magnesium are very similar chemically?
{ "text": [ "ionic radius" ], "answer_start": [ 353 ] }
572b5334111d821400f38e67
Zinc
Zinc chemistry is similar to the chemistry of the late first-row transition metals nickel and copper, though it has a filled d-shell, so its compounds are diamagnetic and mostly colorless. The ionic radii of zinc and magnesium happen to be nearly identical. Because of this some of their salts have the same crystal stru...
Whit what donors does zinc form stable complexes?
{ "text": [ "N- and S-" ], "answer_start": [ 585 ] }
572b5405be1ee31400cb832b
Zinc
Zinc(I) compounds are rare, and require bulky ligands to stabilize the low oxidation state. Most zinc(I) compounds contain formally the [Zn2]2+ core, which is analogous to the [Hg2]2+ dimeric cation present in mercury(I) compounds. The diamagnetic nature of the ion confirms its dimeric structure. The first zinc(I) comp...
What is necessary to stabilize the low oxidation state of zinc(l) compounds?
{ "text": [ "bulky ligands" ], "answer_start": [ 40 ] }
572b5405be1ee31400cb832c
Zinc
Zinc(I) compounds are rare, and require bulky ligands to stabilize the low oxidation state. Most zinc(I) compounds contain formally the [Zn2]2+ core, which is analogous to the [Hg2]2+ dimeric cation present in mercury(I) compounds. The diamagnetic nature of the ion confirms its dimeric structure. The first zinc(I) comp...
What core do most zinc(l) compounds contain?
{ "text": [ "[Zn2]2+" ], "answer_start": [ 136 ] }
572b5405be1ee31400cb832d
Zinc
Zinc(I) compounds are rare, and require bulky ligands to stabilize the low oxidation state. Most zinc(I) compounds contain formally the [Zn2]2+ core, which is analogous to the [Hg2]2+ dimeric cation present in mercury(I) compounds. The diamagnetic nature of the ion confirms its dimeric structure. The first zinc(I) comp...
What confirms the dimeric structure of the compound?
{ "text": [ "diamagnetic nature of the ion" ], "answer_start": [ 236 ] }
572b5405be1ee31400cb832e
Zinc
Zinc(I) compounds are rare, and require bulky ligands to stabilize the low oxidation state. Most zinc(I) compounds contain formally the [Zn2]2+ core, which is analogous to the [Hg2]2+ dimeric cation present in mercury(I) compounds. The diamagnetic nature of the ion confirms its dimeric structure. The first zinc(I) comp...
When a solution of metallic zinc is cooled in molten ZnCl2, what is formed?
{ "text": [ "yellow glass" ], "answer_start": [ 505 ] }
572b550a34ae481900dead8f
Zinc
Binary compounds of zinc are known for most of the metalloids and all the nonmetals except the noble gases. The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric, dissolving in both strong basic and acidic solutions. The other chalcogenides (ZnS, ZnSe, and ZnTe) have v...
What is not known for binary compounds of zinc?
{ "text": [ "noble gases" ], "answer_start": [ 95 ] }
572b550a34ae481900dead90
Zinc
Binary compounds of zinc are known for most of the metalloids and all the nonmetals except the noble gases. The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric, dissolving in both strong basic and acidic solutions. The other chalcogenides (ZnS, ZnSe, and ZnTe) have v...
ZnO can be dissolved in what kind of solutions?
{ "text": [ "strong basic and acidic solutions" ], "answer_start": [ 233 ] }
572b550a34ae481900dead91
Zinc
Binary compounds of zinc are known for most of the metalloids and all the nonmetals except the noble gases. The oxide ZnO is a white powder that is nearly insoluble in neutral aqueous solutions, but is amphoteric, dissolving in both strong basic and acidic solutions. The other chalcogenides (ZnS, ZnSe, and ZnTe) have v...
What applications do chalcogenides have?
{ "text": [ "electronics and optics." ], "answer_start": [ 342 ] }
572b55d7be1ee31400cb8334
Zinc
In weak basic solutions containing Zn2+ ions, the hydroxide Zn(OH) 2 forms as a white precipitate. In stronger alkaline solutions, this hydroxide is dissolved to form zincates ([Zn(OH)4]2−). The nitrate Zn(NO3) 2, chlorate Zn(ClO3) 2, sulfate ZnSO 4, phosphate Zn 3(PO4) 2, molybdate ZnMoO 4, cyanide Zn(CN) 2, arsenite ...
Zn(OH)2 is dissolved to form what in strong alkaline solutions?
{ "text": [ "zincates" ], "answer_start": [ 167 ] }
572b56cd34ae481900dead99
Zinc
The Charaka Samhita, thought to have been written between 300 and 500 AD, mentions a metal which, when oxidized, produces pushpanjan, thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period. The smelting of metallic zinc here, however, appears to have begun around...
Zinc oxide is believed to be mentioned in what ancient text?
{ "text": [ "The Charaka Samhita" ], "answer_start": [ 0 ] }
572b56cd34ae481900dead9a
Zinc
The Charaka Samhita, thought to have been written between 300 and 500 AD, mentions a metal which, when oxidized, produces pushpanjan, thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period. The smelting of metallic zinc here, however, appears to have begun around...
Active zinc mines in India date back to what period?
{ "text": [ "Mauryan period" ], "answer_start": [ 231 ] }
572b56cd34ae481900dead9b
Zinc
The Charaka Samhita, thought to have been written between 300 and 500 AD, mentions a metal which, when oxidized, produces pushpanjan, thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period. The smelting of metallic zinc here, however, appears to have begun around...
What process occurred around the 12th century?
{ "text": [ "smelting of metallic zinc" ], "answer_start": [ 251 ] }
572b56cd34ae481900dead9c
Zinc
The Charaka Samhita, thought to have been written between 300 and 500 AD, mentions a metal which, when oxidized, produces pushpanjan, thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period. The smelting of metallic zinc here, however, appears to have begun around...
When was the Rasaratna Samuccaya written?
{ "text": [ "13th century AD," ], "answer_start": [ 627 ] }
572b56cd34ae481900dead9d
Zinc
The Charaka Samhita, thought to have been written between 300 and 500 AD, mentions a metal which, when oxidized, produces pushpanjan, thought to be zinc oxide. Zinc mines at Zawar, near Udaipur in India, have been active since the Mauryan period. The smelting of metallic zinc here, however, appears to have begun around...
What are the two uses of zinc ore mentioned in the Rasaratna Samuccaya?
{ "text": [ "metal extraction and another used for medicinal purposes" ], "answer_start": [ 701 ] }
572b581a34ae481900deada9
Zinc
The name of the metal was probably first documented by Paracelsus, a Swiss-born German alchemist, who referred to the metal as "zincum" or "zinken" in his book Liber Mineralium II, in the 16th century. The word is probably derived from the German zinke, and supposedly meant "tooth-like, pointed or jagged" (metallic zin...
Who is attributed as first documenting zinc?
{ "text": [ "Paracelsus" ], "answer_start": [ 55 ] }
572b581a34ae481900deadaa
Zinc
The name of the metal was probably first documented by Paracelsus, a Swiss-born German alchemist, who referred to the metal as "zincum" or "zinken" in his book Liber Mineralium II, in the 16th century. The word is probably derived from the German zinke, and supposedly meant "tooth-like, pointed or jagged" (metallic zin...
Why would zinc possibly be derived from the German word zinke?
{ "text": [ "metallic zinc crystals have a needle-like appearance" ], "answer_start": [ 308 ] }
572b581a34ae481900deadab
Zinc
The name of the metal was probably first documented by Paracelsus, a Swiss-born German alchemist, who referred to the metal as "zincum" or "zinken" in his book Liber Mineralium II, in the 16th century. The word is probably derived from the German zinke, and supposedly meant "tooth-like, pointed or jagged" (metallic zin...
Why is it possible that the name zinc could be derived from the German zinn?
{ "text": [ "imply \"tin-like\"" ], "answer_start": [ 379 ] }
572b581a34ae481900deadac
Zinc
The name of the metal was probably first documented by Paracelsus, a Swiss-born German alchemist, who referred to the metal as "zincum" or "zinken" in his book Liber Mineralium II, in the 16th century. The word is probably derived from the German zinke, and supposedly meant "tooth-like, pointed or jagged" (metallic zin...
What are some of the other terms for zinc?
{ "text": [ "Indian tin, tutanego, calamine, and spinter." ], "answer_start": [ 572 ] }
572b5939f75d5e190021fd92
Zinc
William Champion's brother, John, patented a process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques ...
Who first patented the process that creates an oxide usable in the retort process?
{ "text": [ "William Champion's brother, John," ], "answer_start": [ 0 ] }
572b5939f75d5e190021fd93
Zinc
William Champion's brother, John, patented a process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques ...
Before John Champion, what was the only element used to produce zinc?
{ "text": [ "calamine" ], "answer_start": [ 152 ] }
572b5939f75d5e190021fd94
Zinc
William Champion's brother, John, patented a process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques ...
Who built the first horizontal retort smelter?
{ "text": [ "Johann Christian Ruberg" ], "answer_start": [ 201 ] }
572b5939f75d5e190021fd95
Zinc
William Champion's brother, John, patented a process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques ...
What did Galvani name the effect he created of causing the frogs legs to twitch?
{ "text": [ "animal electricity" ], "answer_start": [ 727 ] }
572b5939f75d5e190021fd96
Zinc
William Champion's brother, John, patented a process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques ...
The discoveries made by Galvani lead to what three important things?
{ "text": [ "electrical batteries, galvanization and cathodic protection." ], "answer_start": [ 873 ] }
572b5a02111d821400f38e72
Zinc
Zinc metal is produced using extractive metallurgy. After grinding the ore, froth flotation, which selectively separates minerals from gangue by taking advantage of differences in their hydrophobicity, is used to get an ore concentrate. This concentrate consists of about 50% zinc with the rest being sulfur (32%), iron ...
What is used to produce the metal zinc?
{ "text": [ "extractive metallurgy." ], "answer_start": [ 29 ] }
572b5a02111d821400f38e73
Zinc
Zinc metal is produced using extractive metallurgy. After grinding the ore, froth flotation, which selectively separates minerals from gangue by taking advantage of differences in their hydrophobicity, is used to get an ore concentrate. This concentrate consists of about 50% zinc with the rest being sulfur (32%), iron ...
What is froth flotation used for?
{ "text": [ "get an ore concentrate" ], "answer_start": [ 213 ] }
572b5a02111d821400f38e74
Zinc
Zinc metal is produced using extractive metallurgy. After grinding the ore, froth flotation, which selectively separates minerals from gangue by taking advantage of differences in their hydrophobicity, is used to get an ore concentrate. This concentrate consists of about 50% zinc with the rest being sulfur (32%), iron ...
What is the first step in zinc metal production?
{ "text": [ "grinding the ore" ], "answer_start": [ 58 ] }
572b5a02111d821400f38e75
Zinc
Zinc metal is produced using extractive metallurgy. After grinding the ore, froth flotation, which selectively separates minerals from gangue by taking advantage of differences in their hydrophobicity, is used to get an ore concentrate. This concentrate consists of about 50% zinc with the rest being sulfur (32%), iron ...
What percentage of the ore concentrate is zinc?
{ "text": [ "50%" ], "answer_start": [ 272 ] }
572b5afd34ae481900deadbd
Zinc
The production for sulfidic zinc ores produces large amounts of sulfur dioxide and cadmium vapor. Smelter slag and other residues of process also contain significant amounts of heavy metals. About 1.1 million tonnes of metallic zinc and 130 thousand tonnes of lead were mined and smelted in the Belgian towns of La Calam...
Large amounts of sulfur dioxide and cadmium vapor are produced due to what?
{ "text": [ "The production for sulfidic zinc ores" ], "answer_start": [ 0 ] }
572b5afd34ae481900deadbe
Zinc
The production for sulfidic zinc ores produces large amounts of sulfur dioxide and cadmium vapor. Smelter slag and other residues of process also contain significant amounts of heavy metals. About 1.1 million tonnes of metallic zinc and 130 thousand tonnes of lead were mined and smelted in the Belgian towns of La Calam...
Smelter slag contains a significant amount of what?
{ "text": [ "heavy metals" ], "answer_start": [ 177 ] }
572b5afd34ae481900deadbf
Zinc
The production for sulfidic zinc ores produces large amounts of sulfur dioxide and cadmium vapor. Smelter slag and other residues of process also contain significant amounts of heavy metals. About 1.1 million tonnes of metallic zinc and 130 thousand tonnes of lead were mined and smelted in the Belgian towns of La Calam...
Why does the Geul River contain heavy metals in a significant amount?
{ "text": [ "mining operations leach significant amounts of zinc and cadmium" ], "answer_start": [ 384 ] }
572b5afd34ae481900deadc0
Zinc
The production for sulfidic zinc ores produces large amounts of sulfur dioxide and cadmium vapor. Smelter slag and other residues of process also contain significant amounts of heavy metals. About 1.1 million tonnes of metallic zinc and 130 thousand tonnes of lead were mined and smelted in the Belgian towns of La Calam...
What is the ratio that anthropogenic and natural emissions occur at?
{ "text": [ "20 to 1" ], "answer_start": [ 971 ] }
572b5bab34ae481900deadc5
Zinc
Zinc is more reactive than iron or steel and thus will attract almost all local oxidation until it completely corrodes away. A protective surface layer of oxide and carbonate (Zn 5(OH) 6(CO 3) 2) forms as the zinc corrodes. This protection lasts even after the zinc layer is scratched but degrades through time as the zi...
What two compounds is zinc more reactive than?
{ "text": [ "iron or steel" ], "answer_start": [ 27 ] }
572b5bab34ae481900deadc6
Zinc
Zinc is more reactive than iron or steel and thus will attract almost all local oxidation until it completely corrodes away. A protective surface layer of oxide and carbonate (Zn 5(OH) 6(CO 3) 2) forms as the zinc corrodes. This protection lasts even after the zinc layer is scratched but degrades through time as the zi...
What forms as zinc corrodes?
{ "text": [ "protective surface layer of oxide and carbonate" ], "answer_start": [ 127 ] }
572b5bab34ae481900deadc7
Zinc
Zinc is more reactive than iron or steel and thus will attract almost all local oxidation until it completely corrodes away. A protective surface layer of oxide and carbonate (Zn 5(OH) 6(CO 3) 2) forms as the zinc corrodes. This protection lasts even after the zinc layer is scratched but degrades through time as the zi...
How is zinc applied?
{ "text": [ "electrochemically or as molten zinc" ], "answer_start": [ 358 ] }
572b5bab34ae481900deadc8
Zinc
Zinc is more reactive than iron or steel and thus will attract almost all local oxidation until it completely corrodes away. A protective surface layer of oxide and carbonate (Zn 5(OH) 6(CO 3) 2) forms as the zinc corrodes. This protection lasts even after the zinc layer is scratched but degrades through time as the zi...
What is used on many common items, such as chain link fences?
{ "text": [ "Galvanization" ], "answer_start": [ 430 ] }
572b5c93111d821400f38e7a
Zinc
The relative reactivity of zinc and its ability to attract oxidation to itself makes it an efficient sacrificial anode in cathodic protection (CP). For example, cathodic protection of a buried pipeline can be achieved by connecting anodes made from zinc to the pipe. Zinc acts as the anode (negative terminus) by slowly ...
What makes zinc an efficient sacrificial anode?
{ "text": [ "relative reactivity of zinc and its ability to attract oxidation" ], "answer_start": [ 4 ] }
572b5c93111d821400f38e7b
Zinc
The relative reactivity of zinc and its ability to attract oxidation to itself makes it an efficient sacrificial anode in cathodic protection (CP). For example, cathodic protection of a buried pipeline can be achieved by connecting anodes made from zinc to the pipe. Zinc acts as the anode (negative terminus) by slowly ...
Connecting anodes made from zinc to buried pipe creates what?
{ "text": [ "cathodic protection" ], "answer_start": [ 161 ] }
572b5c93111d821400f38e7c
Zinc
The relative reactivity of zinc and its ability to attract oxidation to itself makes it an efficient sacrificial anode in cathodic protection (CP). For example, cathodic protection of a buried pipeline can be achieved by connecting anodes made from zinc to the pipe. Zinc acts as the anode (negative terminus) by slowly ...
What does attaching a zinc disc to a ships iron rudder do?
{ "text": [ "protect metals that are exposed to sea water from corrosion" ], "answer_start": [ 430 ] }
572b5c93111d821400f38e7d
Zinc
The relative reactivity of zinc and its ability to attract oxidation to itself makes it an efficient sacrificial anode in cathodic protection (CP). For example, cathodic protection of a buried pipeline can be achieved by connecting anodes made from zinc to the pipe. Zinc acts as the anode (negative terminus) by slowly ...
Why does zinc protect metals exposed to sea water from corroding?
{ "text": [ "will slowly corrode, whereas the rudder stays unattacked" ], "answer_start": [ 536 ] }
572b5d6634ae481900deadcd
Zinc
Other widely used alloys that contain zinc include nickel silver, typewriter metal, soft and aluminium solder, and commercial bronze. Zinc is also used in contemporary pipe organs as a substitute for the traditional lead/tin alloy in pipes. Alloys of 85–88% zinc, 4–10% copper, and 2–8% aluminium find limited use in cer...
What has zinc replaced in pipe organs?
{ "text": [ "lead/tin alloy" ], "answer_start": [ 216 ] }
572b5d6634ae481900deadce
Zinc
Other widely used alloys that contain zinc include nickel silver, typewriter metal, soft and aluminium solder, and commercial bronze. Zinc is also used in contemporary pipe organs as a substitute for the traditional lead/tin alloy in pipes. Alloys of 85–88% zinc, 4–10% copper, and 2–8% aluminium find limited use in cer...
Zinc, copper and aluminum alloys have use in what part of machinery?
{ "text": [ "machine bearings" ], "answer_start": [ 334 ] }
572b5d6634ae481900deadcf
Zinc
Other widely used alloys that contain zinc include nickel silver, typewriter metal, soft and aluminium solder, and commercial bronze. Zinc is also used in contemporary pipe organs as a substitute for the traditional lead/tin alloy in pipes. Alloys of 85–88% zinc, 4–10% copper, and 2–8% aluminium find limited use in cer...
Zinc in the main metal used in making which american currency?
{ "text": [ "one cent coins" ], "answer_start": [ 402 ] }
572b5d6634ae481900deadd0
Zinc
Other widely used alloys that contain zinc include nickel silver, typewriter metal, soft and aluminium solder, and commercial bronze. Zinc is also used in contemporary pipe organs as a substitute for the traditional lead/tin alloy in pipes. Alloys of 85–88% zinc, 4–10% copper, and 2–8% aluminium find limited use in cer...
What is zinc coated with to influence the look of pennies?
{ "text": [ "thin layer of copper" ], "answer_start": [ 460 ] }
572b7b86be1ee31400cb83db
Zinc
Alloys of primarily zinc with small amounts of copper, aluminium, and magnesium are useful in die casting as well as spin casting, especially in the automotive, electrical, and hardware industries. These alloys are marketed under the name Zamak. An example of this is zinc aluminium. The low melting point together with ...
Aside from die casting, what are alloys of zinc mixed with copper, aluminium and magnesium used for?
{ "text": [ "spin casting" ], "answer_start": [ 117 ] }
572b7b86be1ee31400cb83dc
Zinc
Alloys of primarily zinc with small amounts of copper, aluminium, and magnesium are useful in die casting as well as spin casting, especially in the automotive, electrical, and hardware industries. These alloys are marketed under the name Zamak. An example of this is zinc aluminium. The low melting point together with ...
Alloys of zinc mixed with copper, aluminium and magnesium are marketed as what?
{ "text": [ "Zamak" ], "answer_start": [ 239 ] }
572b7b86be1ee31400cb83dd
Zinc
Alloys of primarily zinc with small amounts of copper, aluminium, and magnesium are useful in die casting as well as spin casting, especially in the automotive, electrical, and hardware industries. These alloys are marketed under the name Zamak. An example of this is zinc aluminium. The low melting point together with ...
What is possible to produce thanks to the low melting point and low viscosity of zinc aluminium alloy?
{ "text": [ "small and intricate shapes" ], "answer_start": [ 375 ] }
572b7b86be1ee31400cb83de
Zinc
Alloys of primarily zinc with small amounts of copper, aluminium, and magnesium are useful in die casting as well as spin casting, especially in the automotive, electrical, and hardware industries. These alloys are marketed under the name Zamak. An example of this is zinc aluminium. The low melting point together with ...
What brand name of alloy is supposed to be as strong as steel while still being malleable as plastic?
{ "text": [ "Prestal" ], "answer_start": [ 570 ] }
572b7b86be1ee31400cb83df
Zinc
Alloys of primarily zinc with small amounts of copper, aluminium, and magnesium are useful in die casting as well as spin casting, especially in the automotive, electrical, and hardware industries. These alloys are marketed under the name Zamak. An example of this is zinc aluminium. The low melting point together with ...
What is used to mold Prestal?
{ "text": [ "die casts made of ceramics and cement." ], "answer_start": [ 755 ] }
572b7c55be1ee31400cb83e5
Zinc
Similar alloys with the addition of a small amount of lead can be cold-rolled into sheets. An alloy of 96% zinc and 4% aluminium is used to make stamping dies for low production run applications for which ferrous metal dies would be too expensive. In building facades, roofs or other applications in which zinc is used a...
What can be done when small amounts of lead are added to alloys?
{ "text": [ "cold-rolled into sheets" ], "answer_start": [ 66 ] }
572b7c55be1ee31400cb83e6
Zinc
Similar alloys with the addition of a small amount of lead can be cold-rolled into sheets. An alloy of 96% zinc and 4% aluminium is used to make stamping dies for low production run applications for which ferrous metal dies would be too expensive. In building facades, roofs or other applications in which zinc is used a...
What is made with an alloy of 4% aluminium mixed with 96% zinc?
{ "text": [ "stamping dies" ], "answer_start": [ 145 ] }
572b7c55be1ee31400cb83e7
Zinc
Similar alloys with the addition of a small amount of lead can be cold-rolled into sheets. An alloy of 96% zinc and 4% aluminium is used to make stamping dies for low production run applications for which ferrous metal dies would be too expensive. In building facades, roofs or other applications in which zinc is used a...
Why are alloys used to make stamping dies rather than metal?
{ "text": [ "too expensive" ], "answer_start": [ 233 ] }
572b7c55be1ee31400cb83e8
Zinc
Similar alloys with the addition of a small amount of lead can be cold-rolled into sheets. An alloy of 96% zinc and 4% aluminium is used to make stamping dies for low production run applications for which ferrous metal dies would be too expensive. In building facades, roofs or other applications in which zinc is used a...
Why isn't unalloyed zinc used in construction applications?
{ "text": [ "too brittle" ], "answer_start": [ 462 ] }
572b7d1b111d821400f38eb0
Zinc
Roughly one quarter of all zinc output in the United States (2009), is consumed in the form of zinc compounds; a variety of which are used industrially. Zinc oxide is widely used as a white pigment in paints, and as a catalyst in the manufacture of rubber. It is also used as a heat disperser for the rubber and acts to ...
In what form is 1/4 of zinc used in the US?
{ "text": [ "zinc compounds" ], "answer_start": [ 95 ] }