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Is there a way to safely cool a heated test tube quickly without cracking it due to sudden thermal stress in the glass? One thing that I tried was blowing on it, cooling it in slightly lukewarm water followed by cold water but this method kind of involves a "hope for the best factor". Is there a better technique? |
How to quickly cool a test tube without cracking it? |
I have no problem with identifying whether a given molecule has geometrical isomerism if it's not cyclic. But cyclic compounds are confusing for me. For eg: How to check whether the following molecule posses geometrical isomerism?
![enter image description here][1]
[1]: https://i.stack.imgur.com/CYn0d.png
... |
I don't know what identical molecules are but these are by thoughts.
Since from the word identical the molecules should have the same number of carbons attached in the same way. Since in stereo-chemistry the isomerism is due to spacial orientation all stereo-chemical isomers are identical.
Is my thinking correc... |
What are identical molecules? |
Two ways to think about it:
- Intuitively: Take one side of the double bond (say, the sulfur-containing one) and imagine rotating it by 180° (so what was up is now down, in your drawing). Is this molecule the same? If it is, then you don't have isomerism. If the procedure gives a new, different molecule, then you ha... |
How to check for geometrical isomerism in cyclic compounds? |
In the extraction of $\ce{Sn}$ from $\ce{SnO2}$ by carbon reduction method, why is ** $\ce{CO}$ formed instead of $\ce{CO2}$** as per the following reaction?
$\ce{SnO2 + C -> Sn + CO}$ |
In the extraction of $\ce{Sn}$ from $\ce{SnO2}$ by carbon reduction method, why is **$\ce{CO}$ formed instead of $\ce{CO2}$** as per the following reaction?
$\ce{SnO2 + C -> Sn + CO}$ |
Suppose that I have a cast-iron pot which my awful roommate has vigorously scrubbed with soap and left to soak in soapy water over the weekend. The seasoning has been destroyed and replaced with awful-tasting soapy contaminants.
It seems to me that the simplest and best way to deal with this is to heat the pot over ... |
After adding up all the discussion in comments, here is a short generalised answer.
Only count the lone pairs/ pi-bonds/ groups which are participating in conjugation and ignore them in all other cases.
**Like in example D, there are two lone pairs on sulphur between which only one is partcipating in conjugatio... |
The [Clemmensen Reduction](http://en.wikipedia.org/wiki/Clemmensen_reduction) is really only effective at reducing ketones to alkenes when one group is aromatic. Additionally, the Clemmenson Reduction used concentrated HCl, which might cause problems. Do any of the other functional groups in your molecule react with HC... |
$SN^1$ reaction involves only one molecule in the RDS. So, the molecule which undergoes $SN^1$ reaction should be stable when it forms a positive ion.$(CH3)3C^+$ is considered stable due to inductive effect from the three carbon atoms and also hyper-conjugation. But, what about bridged compounds like:
 is really only effective at reducing ketones to alkenes when one group is aromatic. Additionally, the Clemmenson Reduction used concentrated HCl, which might cause problems. Do any of the other functional groups in your molecule react with HC... |
$\mathrm{S}_{\mathrm{N}}1$ reaction involves only one molecule in the RDS. So, the molecule which undergoes $\mathrm{S}_{\mathrm{N}}1$ reaction should be stable when it forms a positive ion. $\ce{(CH3)3C^+}$ is considered stable due to inductive effect from the three carbon atoms and also hyper-conjugation. But, what a... |
Will bridged compounds undergo $S_N1$ reaction? |
$\ce{Cu(NO3)2}(aq)$
So I begin by finding all the species/ions I have:
- $\ce{Cu^{2+}}$
- $\ce{NO3^{-}}$
- $\ce{H2O}$
Taking a look at the `Standard Reduction Potentials at 25°C`:
For my SOA (strongest oxidizing agent) half-reaction ($\ce{NO3^{-}}$):
>$\ce{NO3^{-} + 4H^{+} + 3e^{-} -> NO + 2H2O}$ (E° =... |
$\ce{Cu(NO3)2}(aq)$
There are two copper blocks sitting in the solution, a battery is attached onto both of them, providing enough energy to start the reaction.
So I begin by finding all the species/ions I have:
- $\ce{Cu^{2+}}$
- $\ce{NO3^{-}}$
- $\ce{H2O}$
Taking a look at the `Standard Reduction Potent... |
$\ce{Cu(NO3)2_{(aq)}}$
There are two copper blocks sitting in the solution, a battery is attached onto both of them, providing enough energy to start the reaction.
Since solid pieces of copper are involved, $\ce{Cu}$ must be considered in the reduction potential as well.
However, looking at the half reaction f... |
I'm trying to get the charge on the copper ion in this substance. So far I have the mass of 1 mole, percent oxygen content, and number of individual hydroxide ions in a 955 mg bead of the substance, if that information helps at all. Can you please help me solve this problem ASAP with details and processes? Thank you! |
What is the charge on the copper ion in antlerite which is Cu3(SO4)(OH)4? |
I am burning through some test prep and have a chem question that is troubling me. The questions is as follows:
> How would you compare the acidity of the most acidic proton in each of the following molecules?
1)![enter image description here][1]
2)![enter image description here][2]
3)![enter image desc... |
$\mathrm{S}_{\mathrm{N}}1$ reaction involves only one molecule in the rate determining step. So, the molecule which undergoes $\mathrm{S}_{\mathrm{N}}1$ reaction should be stable when it forms a positive ion. $\ce{(CH3)3C^+}$ is considered stable due to inductive effect from the three carbon atoms and also hyper-conjug... |
After adding up all the discussion in comments, here is a short generalised answer.
Only count the lone pairs/ pi-bonds/ groups which are participating in conjugation and ignore them in all other cases.
**Like in example D, there are two lone pairs on sulphur between which only one is partcipating in conjugatio... |
There is a misunderstanding in the analysis of your first two half-reactions. Your first two half-reactions are fine. Remember that positive values of $E$ mean the reaction is spontaneous. Negative values of $E$ mean the reaction is nonspontaneous, since
$$\Delta_rG=-nFE_{cell}$$
Your first half-reaction is an o... |
Mnemonics help to by-heart things which are difficult to do so and which are important. I found mnemonics for studying the periodic table, electromagnetic series etc which were of great help.So, is there a mnemonic to study the spectrochemical series since knowing it will be of great help to find the geometry of a give... |
Is there a mnemonic to study the spectrochemical series? |
Mnemonics help to by-heart things which are difficult to do so and which are important. I found mnemonics for studying the periodic table, electromagnetic series etc which were of great help.So, is there a mnemonic to study the spectrochemical series since knowing it will be of great help to find the geometry of a give... |
I've to detect the violation of a certain rule or principle in the following electronic configuration:
$1s^2,2s^2,2p^1_x,2p^0_y,2p^0_z$
1) If we test this configuration for $n+l$ rule, then we come to know that the rule is not violated because, for $1s^2$, $n+l=1+0=1$ so it is filled first, for $2s^2$, $n+l=2+0=2... |
Suppose that I have a cast-iron pot which my awful roommate has vigorously scrubbed with soap and left to soak in soapy water over the weekend. The seasoning has been destroyed and replaced with awful-tasting soapy contaminants.
It seems to me that the simplest and best way to deal with this is to heat the pot over ... |
For example the electron configuration for oxygen is 1s<sup>2</sup> 2s<sup>2</sup> 2p<sup>4</sup>. But if an element can never have an element in the p orbital unless it has 2 full s orbitals*, then why can't we write 2p<sup>4</sup> as the electron configuration for oxygen? Is it not implied that it has 1s<sup>2</sup> ... |
Is the electron configuration redundant? |
I have two volatile compounds such as ethyl acetate and ethyl propionate. I am going to separate these compound by simple and fractional distillation. How do I calculate mole ratio of two of the compounds and determine the boiling point temperatures of the first drop based on the liquid and vapor phase diagram?
|
How to calculate mole ratio of two volatile compound in distillation? |
In BeCl2 the number of orbitals on central atom, i.e. on Berrylium are 2. In BF3, the number of orbitals on central atom , i.e. on Boron they are 3. Similarly in NH3 there are 4 , and similarly in PCl5, SF4, ClF3 there are 5. But how? I just dont understand.
Please help. |
HOW TO FIND THE NUMBER OF ORBITALS ON CENTRAL ATOM? |
In $\ce{BeCl2}$ the number of orbitals on central atom, i.e. on beryllium, are 2. In $\ce{BF3}$, the number of orbitals on central atom , i.e. on boron, are 3.
Similarly in $\ce{NH3}$ there are 4, on $\ce{PCl5}$, $\ce{SF4}$, and $\ce{ClF3}$ there are 5. But how? |
Organic semiconductors differ from inorganic semiconductors. In organic semiconductors the molecules are held together by weak van der Waals interactions and in inorganic semiconductors by covalent bonds. So the bonds are different. How do you express the main difference between the twos? Is it the electronic structure... |
Difference between inorganic and organic semiconductors: electronic structure or configuration, or? |
Which element has more metallic character - aluminium or magnesium?
I know that metallic character decreases along a period(from left to right)and increases down a group.
Aluminium comes after Magnesium in the same period(period 3) in the periodical table. So, I thought Magnesium would have greater metallic chara... |
Which is more metallic? |
The energy required to remove both electrons from the helium atom in its ground state is 79.0 eV. The energy required to ionize helium (i.e. to remove one electron) is -
(A) 24/6 eV
(B) 39.5 eV
(C) 51.8 eV
(D) 54.4 eV
My thoughts:What I actually did was to take half of the given energy value since energ... |
Which element has more metallic character - aluminium or magnesium?
I know that metallic character decreases along a period(from left to right)and increases down a group.
Aluminium comes after Magnesium in the same period (period 3) in the periodic table. So, I thought Magnesium would have greater metallic charac... |
The hair gel is called "lets Jam Gel". It says it uses micro emulsion technology.
What chemicals can you use to break it down or undo the bonds? |
What can you move to remove hair gel? |
Yes, you are right that $\ce{Al}$ is more metallic than $\ce{Mg}$.
It is because, **$\ce{Mg}$ have fully filled $3\text{s}$ subshell**. Due to this, the first [ionisation energy][1] of $\ce{Al}$ (578 kJ/mol) is less than that of $\ce{Mg}$ (738 kJ/mol).
You can also say that higher levels of subshells are further a... |
The hair gel is called "lets Jam Gel". It says it uses micro emulsion technology.
What chemicals can you use to break it down or undo the bonds?
I'm trying to get it out of my head. I washed my hair with T sal and cut my hair off but it still grows back patchy and easy to style like it has gel in it.
ingredients... |
The hair gel is called "lets Jam Gel". It says it uses micro emulsion technology.
What chemicals can you use to break it down or undo the bonds?
I'm trying to get it out of my head. I washed my hair with T sal and cut my hair off but it still grows back patchy and easy to style like it has gel in it. I think it may... |
Is there an appropriate alternative to DMSO? I mean for embryo or oocyte freezig?
I am a PhD student at present. i am going to study on this substance and im very interested to this field.
Best regard. |
an alternative to DMSO? |
Is there an appropriate alternative to DMSO? I mean for embryo or oocyte freezing?
I am a PhD student at present. I am going to study this substance and I'm very interested in this field. |
An alternative to dimethylsulfoxide (DMSO) for cryoprotection? |
The energy required to remove both electrons from the helium atom in its ground state is 79.0 eV. The energy required to ionize helium (i.e. to remove one electron) is -
(A) 24/6 eV
(B) 39.5 eV
(C) 51.8 eV
(D) 54.4 eV
My thoughts: What I actually did was to take half of the given energy value since ener... |
What can you use to remove hair gel? |
I have learnt that only chiral or unsymmetrical molecules can rotate plane polarized light. But, why is it so?
And how can molecules rotate plane polarized light or what does it actually mean by 'rotating'?
Does it mean that the electric field vectors are tilted or turned left or right depending on the type of iso... |
Why only chiral molecules rotate plane polarized light and how does it rotate light? |
The energy required to remove both electrons from the helium atom in its ground state is $79.0\;\mathrm{eV}$. The energy required to ionize helium (i.e. to remove one electron) is -
(A) $24.6\;\mathrm{eV}$
(B) $39.5\;\mathrm{eV}$
(C) $51.8\;\mathrm{eV}$
(D) $54.4\;\mathrm{eV}$
My thoughts: What I actual... |
See also: [How do Optically Active Compounds Rotate Plane Polarized Light?][1]
This is because optical rotation is a chiral phenomenon.
Take a molecule, and draw arrows depicting the polarization of incoming and outgoing light on it. Even if the molecule is achiral, the molecule with the arrows is chiral.
Chi... |
What I understand by spontaneous reaction is that - A reaction whose G is -ve and which occurs without input of energy.
Gasoline reacts with oxygen only if a spark is provided. So how can it be a spontaneous reaction ?
Do non spontaneous reactions occur in nature ? If so, are they always slow ? If they are slow ... |
So, I was doing my homework and had to write out the complete equation and net ionic equation for a combination of Lead (II) Iodate and Sodium Hydroxide.
So my equation is given as:
$$Pb(IO_3)_{2(aq)} + NaOH_{(aq)} - > ???$$
However my dilemma is that both of these compounds *seem* to be insolvable and I'm not... |
How do I write the complete and net ionic equations for Insoluble compounds? |
So, I was doing my homework and had to write out the complete equation and net ionic equation for a combination of Lead (II) Iodate and Sodium Hydroxide.
So my equation is given as:
$\ce{Pb(IO3)2_{(aq)} + NaOH_{(aq)} -> ?}$$
However my dilemma is that both of these compounds *seem* to be insolvable and I'm not... |
So, I was doing my homework and had to write out the complete equation and net ionic equation for a combination of Lead (II) Iodate and Sodium Hydroxide.
So my equation is given as:
$\ce{Pb(IO3)2_{(aq)} + NaOH_{(aq)} -> ?}$
However my dilemma is that both of these compounds *seem* to be insolvable and I'm not ... |
So I plan to do a string of experiments on the kinetics of the decomposition of hydrogen peroxide. I'm going to see the effect of catalyst concentration on rate and the effect of varying hydrogen peroxide concentration on rate, which will then allow me to formulate a rate equation for the reaction.
However, I would... |
How can I go about obtaining the activation enthalpy of a reaction using the Arrhenius Equation experimentally? |
It seems that most people draw ClO4- with three double bonds and the negative charge on the oxygen:
http://www.chemspider.com/Chemical-Structure.109953.html
However, it would seem that it is more stable for the negative charge to be on the chlorine as it is more electronegative? (thus giving 4 double bonds to each ... |
Why does ClO4- only have 3 double bonds? |
It seems that most people draw $\ce{ClO4^{-}}$ with three double bonds and the negative charge on the oxygen:
http://www.chemspider.com/Chemical-Structure.109953.html
However, it would seem that it is more stable for the negative charge to be on the chlorine as it is more electronegative? (thus giving 4 double bond... |
Why does $\ce{ClO4^{-}}$ only have 3 double bonds? |
Why does ClO4- only have 3 double bonds? |
I learnt that all strong acids have a 100% degree of ionisation and that there are no degrees of strength in acids but I also read that fluoroantimonic acid is 20 quintillion times stronger than 100% sulfuric acid ?!?!?!?!?
Can you please explain the chemistry behind this? |
Why is fluoroantimonic acid so strong? |
What product will get when sucrose and potassium nitrate mix burn in combusted container? (Smoke Bomb) KNO3+C12H22O11=? |
What product will get when sucrose and potassium nitrate mix burn? |
You will get Potassium carbonate ($\ce{K2CO3}$), Carbon dioxide ($\ce{CO2}$), Water ($\ce{H2O}$) & Nitrogen gas ($\ce{N2}$) as per the following reaction.
$\ce{48KNO3 + 5C12H22O11 -> 24K2CO3 + 36CO2 + 55H2O + 24N2}$
See [this][1] & [this][2].
[1]: http://answers.yahoo.com/question/index?qid=20110505190952AAG... |
What product will get when sucrose and potassium nitrate mix burn in combusted container? (Smoke Bomb)
$\ce{KNO3 + C12H22O11 -> ?}$ |
I plan to do a string of experiments on the kinetics of the decomposition of hydrogen peroxide. I'm going to see the effect of catalyst concentration on rate and the effect of varying hydrogen peroxide concentration on rate, which will then allow me to formulate a rate equation for the reaction.
I would also like t... |
![enter image description here][1]
[1]: https://i.stack.imgur.com/kK6ih.jpg
I was hoping I could get help finding ways to sort information in the problem. What kind of information does "the conversion of toluene to benzene..." give us that is relevant towards solving the problem for values $R_G$ and $R_L$? |
From your diagram, $R_G$ is the recycled gas - the hydrogen that has not been consumed plus the methane that has been produced. $R_L$ is the recycled liquid - the unreacted toluene. Both go back into the mixer with fresh toluene added at the rate given and fresh hydrogen added to bring the mole ratio of hydrogen to tol... |
Are there positive ligands which can bind to the central metal atom to form co-ordination compounds?
$My$ $thoughts:$I know that ligands are Lewis bases which donate a pair of electrons and the central metal will be a lewis acid. So, positive ligand means it is deficient of electrons.
In that case there is no elect... |
Are there positive ligands? |
I learnt that all strong acids have a 100% degree of ionisation and that there are no degrees of strength in acids but I also read that fluoroantimonic acid is **20 quintillion** times stronger than 100% sulfuric acid ?!?!?!?!?
Can you please explain the chemistry behind this? |
Consider the reaction, 2A + B -> Products. When concentration of B alone was doubled, half life did not changed. When concentration of A alone was doubled, the rate increased by two times. The unit of Rate constance is :
a) $s^{-1}$
b) $L mol^{-1} s^{-1}$
c) Unitless
d) $mol L^{-1} s^{-1}$
I have tried... |
Find the unit of Rate Constant? |
Consider the reaction, $\ce{2A + B -> \text{Products}}$. When concentration of B alone was doubled, half life did not changed. When concentration of A alone was doubled, the rate increased by two times. The unit of Rate constance is :
a) $s^{-1}$
b) $L mol^{-1} s^{-1}$
c) Unitless
d) $mol L^{-1} s^{-1}$
... |
Consider the reaction, $\ce{2A + B -> Products}$. When concentration of B alone was doubled, half life did not changed. When concentration of A alone was doubled, the rate increased by two times. The unit of Rate constance is :
a) $s^{-1}$
b) $L mol^{-1} s^{-1}$
c) Unitless
d) $mol L^{-1} s^{-1}$
I hav... |
I've graphed a distillation curve (temperature against volume of distillate) from the data obtained from a simple distillation experiment. The substance can be any of methanol, ethanol, 1-propanol or a 1-propanol and water azeotrope).
How can I find the boiling point from this curve to determine the identity of th... |
How can I determine the boiling point of a compound using simple distillation? |
I've graphed a distillation curve (temperature against volume of distillate) from the data obtained from a simple distillation experiment. The substance can be any of methanol, ethanol, 1-propanol or a 1-propanol and water azeotrope).
How can I find the boiling point from this curve to determine the identity of th... |
![Question][1]
Compound I is obviously the Z isomer. I thought it was obviously the less stable one too, given that there's a phenyl and t-butyl on the same side. The answer says that since the phenyl is planar, it actually exhibits less steric hindrance than a methyl group.
Is this because the phenyl ring is pla... |
sorry may be some terms used in the question are not correct and may be this is a trivial question, but I'm not a chemist I am a computer scientist.
In a liquid crystal cell used for LCD the conductive substrates, usually made of ITO, are in contact with the liquid crystal. The question is: when a voltage is applied t... |
![Question][1]
Compound I is obviously the Z isomer. I thought it was obviously the less stable one too, given that there's a phenyl and t-butyl on the same side. The answer says that since the phenyl is planar, it actually exhibits less steric hindrance than a methyl group.
Is this because the planar phenyl ring... |
The stoichiometric defects (Schottky and Frenkel defects) in ionic crystals are formed due to irregularities in ionic arrangement all the while maintaining the stoichiometry and electric neutrality. But $\ce{AgBr}$ shows both Frenkel and Schottky defects while most other compounds show only one of these defects. $\ce{... |
Stoichiometric defects in ionic crystal? |
Do you mean that the substance could be pure methanol, ethanol or 1-propanol?
In that case there is a simple way to distinguish between the four options. A pure substance will have a T-V curve that consists of 2 straight lines, 1 running from $T=T_{start}$ to $T=T_{b}$ at $V=0$ and one running from $V=0$ to $V=V_{t... |
Sorry, maybe some terms used in the question are not correct and may be this is a trivial question, but I'm not a chemist I am a computer scientist.
In a liquid crystal cell used for LCD the conductive substrates, usually made of [ITO][1], are in contact with the liquid crystal. The question is: when a voltage is appl... |
The stoichiometric defects ([Schottky][1] and [Frenkel][2] defects) in ionic crystals are formed due to irregularities in ionic arrangement all the while maintaining the stoichiometry and electric neutrality. But $\ce{AgBr}$ shows both Frenkel and Schottky defects while most other compounds show only one of these defe... |
Organic semiconductors differ from inorganic semiconductors. In organic semiconductors the molecules are held together by weak van der Waals interactions and in inorganic semiconductors by covalent bonds. So the bonds are different. How do you express the main difference between the twos? Is it the electronic structure... |
What is the role of hydrochloric acid in a copper electroplating bath? |
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