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Why LiAlH(O-t-bu)3 doesn't reduce acidic chloride to alcohol? |
Why when a ring has 8 carbon's and contains a double bond the trans version is very unstable to exist, for instance a molecule like cholesterol? |
Why can't the trans version exist? |
CH3-COCl + LiAlH4 + H2O ---> CH3-CH=O ----> CH3-CH2-OH
but,
CH3-COCl + LiAlH(O-t-bu)3 + H2O ---> CH3-CH=O ----> but doesn't reduce further
**Why do LiAlH(O-t-bu)3 and similar bulky reducing agents don't reduce acidic chlorine further?**
|
$$\ce{CH3-COCl + LiAlH4 + H2O -> CH3-CH=O -> CH3-CH2-OH}$$
but,
$$\ce{CH3-COCl + LiAlH(O-t-bu)3 + H2O -> CH3-CH=O ->}$$ but doesn't reduce further
**Why do $\ce{LiAlH(O-t-bu)3}$ and similar bulky reducing agents don't reduce acidic chlorine further?**
|
Why do $\ce{LiAlH(O-^{t}Bu)3}$ and similar bulky reducing agents not reduce acidic chlorine further?
$$\ce{CH3-COCl + LiAlH4 + H2O -> CH3-CH=O -> CH3-CH2-OH},$$
but
$$\ce{CH3-COCl + LiAlH(O-^{t}Bu)3 + H2O -> CH3-CH=O -> no~reaction}.$$
|
Why does LiAlH(O-tert-Bu)3 not reduce acyl chlorides to alcohols? |
Artificially grown bismuth crystals are arguably magnificent, as seen in the image below:
![enter image description here][1]
Image source: [Minerals.net][2]
The website states that:
> They have hopper-like growths in pseudocubic crystals, and are usually coated with chemicals to prevent tarnish, thus mainta... |
What causes the iridescent colour in laboratory grown bismuth? |
So, I've been looking into polymer chemistry to model breaking polymers for a biological model, and I've been a bit stumped by the concept of persistence length.
I know that if a polymer is significantly longer than its persistence length, it needs to be treated as though the ends are completely independent of each ... |
Most heat capacities go through a maximum as the temperature increases. $C_V = \left( \frac{dU}{dT} \right)_V$ so a maximum in $C_V$ corresponds to a minimum in $\left( \frac{dT}{dU} \right)_V$, i.e. the point where the temperature changes very little as energy is being supplied to the system. At this point (most of) ... |
Most heat capacities go through a maximum as the temperature increases. $C_V = \left( \frac{dU}{dT} \right)_V$ so a maximum in $C_V$ corresponds to a minimum in $\left( \frac{dT}{dU} \right)_V$, i.e. the point where the temperature changes very little as energy is being supplied to the system. At this point (most of) ... |
Why can't small trans-cycloalkenes exist? |
Group 11 metals namely $\ce{Cu, Ag, Au}$ are known for their low reactivities. They are thus rightly called coinage metals and have been historically used to make currency owing to this very property of theirs. My question is, what is the reason behind this behaviour?
Is it because of the stability of fully filled ... |
Why are Group 11 elements unreactive? |
The first question to always ask when you are trying to build an MO diagram is what point group does my molecule fall into? In this case, the $\ce{CH2}$ molecule has C2V symmetry (like the water example shown above). Each of the atomic orbitals (AO's) on carbon (left) and the combination of $1s$ orbitals on the hydro... |
So I'm getting started into Chemistry:
> $$2NH_3+CO_2 \implies (NH_2)_2CO+H_2O$$
>
> If we have $637.2g$ of $NH_3$ and $1142,0$ of $CO_2$ how many grams of
> $(NH_2)_2CO$ will we get?
This is the explanation I was given:
> First, convert reactives to moles:
>
> - $637,2g$ of $NH_3$ are $37.5$ moles.
>... |
So I'm getting started into Chemistry:
> $$\ce{2NH_3 + CO_2 \implies (NH_2)_2CO + H_2O}$$
>
> If we have $637.2g$ of $\ce{NH_3}$ and $1142,0$ of $\ce{CO_2}$ how many grams of
> $\ce{(NH_2)_2CO}$ will we get?
This is the explanation I was given:
> First, convert reactives to moles:
>
> - $637,2g$ of $\c... |
I’m not sure if this answering attempt is correct in the light of Mithoron’s and ron’s comments on your question, but this is the way I learnt it, so if this is wrong I will at least learn something, too.
We all know what s-, p- and d-orbitals look like, but what is the significance, and why do these orbitals prefer... |
I have a molecule extracted from the PDB. When I load it into Avogadro, is placed some bond types wrong. I want to correct this, by setting the bond type (single, double) for these bonds. How can I do this? |
How can I change the bond type (single, double) of an existing bond in Avogadro? |
These huge arrows are very annoying to me. I disable them every time I open Avogadro. Is there a way to disable them permanently? |
Can I disable "Display visual cues" by default in Avogadro? |
I understand that it is possible to cool a liquid past its freezing point, and still maintain its liquid state because crystallisation would not happen in the absence of a seed crystal.
My questions
A) why is such a nucleation event necessary in the first place? Does it arise out of some theoretical calculations... |
Group 11 metals namely $\ce{Cu, Ag, Au}$ are known for their low reactivities. They are thus rightly called coinage metals and have been historically used to make currency owing to this very property of theirs. My question is, what is the reason behind this behaviour?
Is it because of the stability of fully filled ... |
I understand that it is possible to cool a liquid past its freezing point, and still maintain its liquid state because crystallisation would not happen in the absence of a seed crystal.
My question, was marked as a duplicate and I was linked to to [Can all substances be supercooled?][1]
One of the answers over th... |
The final paragraph of Dissenter's question [here][1] is worthy of standing alone:
> [H]ow does one square a high heat of vaporization with a low boiling point? If it takes a lot of energy to vaporize something, then how can that something have a low boiling point?
(It's similar to [this][2] old question by Frie... |
How is it possible for a substance to have a high heat of vaporization but a low boiling point? |
This seeming contradiction can be reconciled by examining the thermodynamic quantities involved. First, per [Wikipedia][1], the *enthalpy of vaporization* is "the enthalpy change required to transform a given quantity of a substance from a liquid into a gas at a given pressure." Written symbolically:
$$
\Delta H_... |
How would you go about writing the reaction between water and chromium metal under standard acid and base conditions?
I know you would have to look at the vertical lines at ph 0 and 14 but I dont know how you would know which species to look at and whether or not you write the reduction or oxidation of water.
Als... |
How would you go about writing the reaction between water and chromium metal under standard acid and base conditions?
I know you would have to look at the vertical lines at pH 0 and 14 but I don't know how you would know which species to look at and whether or not you write the reduction or oxidation of water.
Al... |
So I'm getting started into Chemistry:
> $$\ce{2NH3 + CO2 -> (NH2)2CO + H2O}$$
>
> If we have $637.2\ \mathrm{g}$ of $\ce{NH3}$ and $1142.0\ \mathrm{g}$ of $\ce{CO2}$ how many grams of $\ce{(NH2)2CO}$ will we get?
This is the explanation I was given:
> First, convert reactives to moles:
>
> - $637.2\ \m... |
In one of my chemistry revision papers,there was a question saying,
What would happen when you mix liquid NH3 and excess of sulphur.They say a solid with N and S and a gas which gives a black precipitate with lead acetate is evolved.
Surely, H2S gas will evolve.What about the solid?Is it ammonium sulphide or am... |
In one of my chemistry revision papers,there was a question saying,
What would happen when you mix liquid $\ce{NH3}$ and excess of sulphur. They say a solid with $\ce{N}$ and $\ce{S}$ and a gas which gives a black precipitate with lead acetate is evolved.
Surely, $\ce{H2S}$ gas will evolve. What about the solid... |
In one of my chemistry revision papers,there was a question saying
> What would happen when you mix liquid $\ce{NH3}$ and excess of sulphur?
They say a solid with $\ce{N}$ and $\ce{S}$ and a gas which gives a black precipitate with lead acetate is evolved.
Surely, $\ce{H2S}$ gas will evolve. What about the ... |
What's the solid product of the reaction of ammonia with sulfur? |
More specifically, the expression for the average expectation value of the transverse magnetization has the following form:
$M^+(t)=N\gamma \hbar \text{Tr}(\hat{\sigma}(t)\hat{F}^+)$
with $\hat{\sigma}(t)$ the density matrix. $\hat{F}^+$ is defined as:
$\hat{F}^+=\displaystyle \sum ^{K} _{k=1} \hat{I}^+ _k=\su... |
Did anyone explain why you convert to moles? It is because moles is a certain quantity of molecules of and to balance the equation you need to work in molecules or molecule multiples.
So if it goes to completion you will use up all of the $\ce{NH3}$ as you say, but be left with 7.25 moles of $\ce{CO2}$, 18.75 moles... |
More specifically, the expression for the average expectation value of the transverse magnetization has the following form:
$$M^+(t)=N\gamma \hbar \text{Tr}(\hat{\sigma}(t)\hat{F}^+)$$
with $\hat{\sigma}(t)$ the density matrix. $\hat{F}^+$ is defined as:
$$\hat{F}^+=\displaystyle \sum ^{K} _{k=1} \hat{I}^+ _k=... |
I have used iodomethane to make a phenolic OH group to OMe group in Aq+Methanol medium. i have added water to precipitate the product of mine and will evaporate the solvents but I cant use rotavap until i am sure that any residual iodomethane is not contaminating the condenser of rotavap. How shall i destroy excess iod... |
how to destroy excess iodomethane in reaction mixture? |
$K_p$ is defined as $\Pi_j(\frac{P_j}{P^{\Theta}})^{\nu j}$ where $P_j$ is the partial pressure of component j and $\nu$ is the stoichiometric coefficient. I have a couple of questions already. Firstly, $K_p$ is meant to be dimensionless so therefore, $\frac{P_j}{P^{\Theta}}$ must be dimensionless. However, surely $P_j... |
How would you go about writing the reaction between water and chromium metal under standard acid and base conditions?
I know you would have to look at the vertical lines at pH 0 and 14 but I don’t know how you would know which species to look at and whether or not you write the reduction or oxidation of water.
Al... |
Pressure holds a great significance when it comes to reactions involving gaseous species. Changing pressure can affect the kinetics and even mechanisms of such reactions. <p>
However, ***does pressure hold any significance in reactions involving solid and liquid reactants only?***
<br>
*Examples, if any, would be... |
Does Pressure affect non-gaseous reactions? |
$K_p$ is defined as $\Pi_j(\frac{P_j}{P^{\Theta}})^{\nu j}$ where $P_j$ is the partial pressure of component j and $\nu$ is the stoichiometric coefficient. I have a couple of questions already. Firstly, $K_p$ is meant to be dimensionless so therefore, $\frac{P_j}{P^{\Theta}}$ must be dimensionless. However, surely $P_j... |
The hydrogen in C4, C6, C10 and C8 belong to same hydrogen environment.
The hydrogen in C3, C1, C11 and C13 belong to the another hydrogen environment.
And hydrogen in C12 and C2 belong to the once again, another hydrogen environment.
My question is C3, C1 , C11 C13, C12 and C2 all have two hydrogen in the neighbor... |
**Problem:** Calculate the reaction-enthalpy for the synthesis of $40$ g hydrazine (rocketfuel): $$\ce{4 NH_3 (g) + Cl_2 (g) -> N_2 H_4 (l) + 2 NH_4 Cl (s)}$$
**Attempt at solution:** First we have to account for the decomposition of four moles of ammonia into its elements. Since $\Delta H_f^o$ for $\ce{NH_3}$ is $-... |
Here are the electron affinities of the 17th and 18th groups.
![enter image description here][1]
[1]: https://i.stack.imgur.com/ycQRj.png
The general trend for electron affinity down the group is that it decreases because of the increase in atomic radius.The exception of Cl>F, I can understand is because ... |
I tried to google and watch youtube videos on how to do lewis structures properly, but I cant seem to understand how to do this properly.
My teacher, when class was in session, gave me a set of instructions to complete Lewis structures:
1)Sum Valence electrons
2)add electrons to outer atoms, while
... |
This seeming contradiction can be reconciled by examining the thermodynamic quantities involved. First, per [Wikipedia][1], the *enthalpy of vaporization* is "the enthalpy change required to transform a given quantity of a substance from a liquid into a gas at a given pressure." Written symbolically:
$$
\Delta H_... |
I tried to google and watch youtube videos on how to do lewis structures properly, but I cant seem to understand how to do this properly.
My teacher, when class was in session, gave me a set of instructions to complete Lewis structures:
1. Sum Valence electrons
2. Add electrons to outer atoms, while obeying ... |
I was wondering that like whenever I boil milk I just have to keep standing in front of it to make sure that I don't waste any milk but then I was wondering like Why does it even overflow ? In case of water it doesn't happen. What makes it to behave like this ? |
Why does milk overflow when boiled? |
I tried to google and watch youtube videos on how to do lewis structures properly, but I cant seem to understand how to do this properly.
My teacher, when class was in session, gave me a set of instructions to complete Lewis structures:
1. Sum Valence electrons
2. Add electrons to outer atoms, while obeying ... |
I tried to google and watch youtube videos on how to do lewis structures properly, but I cant seem to understand how to do this properly.
My teacher, when class was in session, gave me a set of instructions to complete Lewis structures:
1. Sum Valence electrons
2. Add electrons to outer atoms, while obeying ... |
Here are the electron affinities of the 17th and 18th groups.
![enter image description here][1]
[1]: https://i.stack.imgur.com/ycQRj.png
The general trend for electron affinity down the group is that it decreases because of the increase in atomic radius.The exception of $\ce{Cl>F}$, I can understand is b... |
Does pressure affect non-gaseous reactions? |
The hydrogen in $\ce{C4}$, $\ce{C6}$, $\ce{C10}$ and $\ce{C8}$ belong to same hydrogen environment.
The hydrogen in $\ce{C3}$, $\ce{C1}$, $\ce{C11}$ and $\ce{C13}$ belong to the another hydrogen environment.
Hydrogen in $\ce{C12}$ and $\ce{C2}$ belong to the once again, another hydrogen environment.
My quest... |
> Why can there not be more than one sigma bond in a set of bonds?
There can be, even in simple carbon compounds. [Bent bonds, tau bonds or banana bonds][1]; whatever you might like to call them were proposed by Linus Pauling; Erich Hückel proposed the alternative $\sigma - \pi$ bonding formalism. Hückel's descripti... |
$K_p$ is defined as $\Pi_j(\frac{P_j}{P^{\Theta}})^{\nu j}$ where $P_j$ is the partial pressure of component j and $\nu$ is the stoichiometric coefficient. I have a couple of questions already. Firstly, $K_p$ is meant to be dimensionless so therefore, $\frac{P_j}{P^{\Theta}}$ must be dimensionless. However, surely $P_j... |
I have used iodomethane to make a phenolic $\ce{OH}$ group to $\ce{OMe}$ group in Aq+Methanol medium. I have added water to precipitate the product of mine and will evaporate the solvents but I cant use rotavap until I am sure that any residual iodomethane is not contaminating the condenser of rotavap. How shall I dest... |
> Why can there not be more than one sigma bond in a set of bonds?
There can be, even in simple carbon compounds. [Bent bonds, tau bonds or banana bonds][1]; whatever you might like to call them were proposed by Linus Pauling; Erich Hückel proposed the alternative $\sigma - \pi$ bonding formalism. Hückel's descripti... |
> Why can there not be more than one sigma bond in a set of bonds?
There can be, even in simple carbon compounds. [Bent bonds, tau bonds or banana bonds][1]; whatever you might like to call them were proposed by Linus Pauling; Erich Hückel proposed the alternative $\sigma - \pi$ bonding formalism. Hückel's descripti... |
I've had already been aware of the fact that metallic aluminum can be degraded by coming in contact with mercury, but also came across another question more recently [here][1] explains a similar reaction with liquid gallium.
So my question is more general regarding corrosive action of *any* liquid metal on other met... |
What are the conditions for liquid metal to be corrosive to another, different solid metal? |
I've had already been aware of the fact that metallic aluminum can be degraded by coming in contact with mercury, but also came across another question more recently [here][1] explains a similar reaction with liquid gallium.
So my question is more general regarding corrosive action of *any* liquid metal on other met... |
This seeming contradiction can be reconciled by examining the thermodynamic quantities involved. First, per [Wikipedia][1], the *enthalpy of vaporization* is "the enthalpy change required to transform a given quantity of a substance from a liquid into a gas at a given pressure." Written symbolically:
$$
\Delta H_... |
***TL;DR Ionic bonds seem to be physical bonds but are classified as chemical bonds***
> "Ionic bonding is a type of chemical bond that involves the electrostatic attraction between oppositely charged ions." - *Wikipedia, definition of an ionic bond*
> "The physical force of attraction which holds atoms and mole... |
Why is an ionic bond a chemical bond? |
Why is HNO3 a stronger oxidising agent than H3PO4? N and P have the same oxidation number. Is it the electronegativity difference between N and P? Thanks. |
Why is HNO3 a stronger oxidising agent than H3PO4? |
This seeming contradiction can be reconciled by examining the thermodynamic quantities involved. First, per [Wikipedia][1], the *enthalpy of vaporization* is "the enthalpy change required to transform a given quantity of a substance from a liquid into a gas at a given pressure." Written symbolically:
$$
\Delta H_... |
Supercooling (and superheating) occur mainly due to the difference between surface energy and volume energy. An intersection of two phases/compounds has higher energy than a bulk material.
For example, the interface of ice and water has higher energy because frozen liquid molecules are favored by entropy to mix with... |
The hydrogen in $\ce{C4}$, $\ce{C6}$, $\ce{C10}$ and $\ce{C8}$ belong to same hydrogen environment.
The hydrogen in $\ce{C3}$, $\ce{C1}$, $\ce{C11}$ and $\ce{C13}$ belong to the another hydrogen environment.
Hydrogen in $\ce{C12}$ and $\ce{C2}$ belong to the once again, another hydrogen environment.
$\ce{C3}... |
A question on an exam asked why there is exactly one sigma bond in double and triple covalent bonds. I looked in my text and online after the exam, but couldn't find an anawer to the question.
Why can there not be more than one sigma bond in a set of covalent bonds? |
Why is $\ce{HNO3}$ a stronger oxidising agent than $\ce{H3PO4}$? $\ce{N}$ and $\ce{P}$ have the same oxidation number. Is it the electronegativity difference between $\ce{N}$ and $\ce{P}$? |
Ionic bonds seem to be physical bonds but are classified as chemical bonds.
> "Ionic bonding is a type of chemical bond that involves the electrostatic attraction between oppositely charged ions." - *Wikipedia, definition of an ionic bond*
> "The physical force of attraction which holds atoms and molecules in a ... |
Why is an ionic bond a chemical and not a physical bond? |
How to find equivalent weight of acid if given that 1.321gm acid reacts with magnesium to give 1.72gm salt? |
> How to find equivalent weight of acid if given that 1.321gm acid
> reacts with magnesium to give 1.72gm salt? |
> 1) Why is only triphenyl phosphine used here. Why not some stronger
> nucleophile like say trimethyl phosphine?
Trialkyl phosphines can particpate in the Wittig reaction just fine, but they create some other problems. Let's say you were going to create the phosphonium salt from ethyl iodide and trimethyl phosphi... |
*Ok so this is the proposed mechanism for the Wittig Reaction as stated by my textbook, LG Wade. I have some doubts regarding this mechanism:*
![enter image description here][1]
![enter image description here][2]
> 1) Why is only triphenyl phosphine used here. Why not some stronger
> nucleophile like ... |
CaCO3(S)->CaO(S)+CO2(g) delta H*=+556 KJ/mol (endothermic)
How will the equilibrium partial pressure of CO2 be effected if the volume is decreased?
So, I thought come on fancy pants! it's easy as a piece of cake, of course the moles will increase when you decrease the volume hence PV=nRT thus P=(nRT)/V . T... |
**Short version:**
We don't call bonds "physical", there are chemical bonds and other types of interactions between particles. The chemical bonds are classified this way because they make up molecules, salts, polymers and such, which are the materials chemists are interested in studying, and not particularly because... |
$\ce{CaCO3(s)->CaO(s) +CO2(g)}$ $\Delta H* = +556 \ce{KJ/mol}$ (endothermic)
How will the equilibrium partial pressure of $\ce{CO2}$ be effected if the volume is decreased?
So, I thought of course the moles will increase when you decrease the volume hence $PV = nRT$, thus $P = \frac{nRT}{V}$ . Therefore, $... |
Okay let's recall what the Le Châtelier's principle is all about: (in short) whenever a system in equilibrium is disturbed the system will adjust itself in such a way that the effect of the change will be nullified.
Now let's look at your problem:
$\ce{CaCO3(s)->CaO(s) +CO2(g)}$ $\Delta H* = +556 \ce{KJ/mol}$ (e... |
If a bangle is made out of gold and silver, connected with each-other would there be a corrosion happening?
If so can it be explained using the galvanic series?
Also do those metals undergo oxidation under normal conditions?
Thankx
|
If a bangle is made out of gold and silver, connected with each-other would there be corrosion happening?
If so, can it be explained using the galvanic series?
Also do those metals undergo oxidation under normal conditions?
|
Why are triflates so widely used in coupling reactions, but not tosylates, mesylates nor nosylates? |
> How to find equivalent weight of acid if given that 1.321 g acid
> reacts with magnesium to give 1.72 g salt? |
$\ce{CaCO3(s) -> CaO(s) + CO2(g)}\quad\Delta H^\circ = +556\ \mathrm{kJ/mol}$ (endothermic)
How will the equilibrium partial pressure of $\ce{CO2}$ be effected if the volume is decreased?
So, I thought of course the moles will increase when you decrease the volume hence $pV = nRT$, thus $p = \frac{nRT}{V}$. Th... |
While studying about bonding there was one statement written that "Pi bond can only be formed only in formation to sigma bond" as we know that in double bond there is 1 sigma bond and 1 Pi bond but then one question arises that Why pi bond is formed only in formation to sigma bond ? Is it possible to form Pi bond witho... |
Why pi bond is formed only in formation to sigma bond? |
While doing Titration we are instructed to use pipette and they show us the demonstration to how to use pipette. But still after all this we face difficulty of how to take precise reading from pipette.
Example-
1. Due to concave water meniscus so till where to take reading ?
2. Is it really important to take ever... |
How to get precise reading from pipette? |
While doing titrations, we are instructed to use pipette and they demonstrated how to use a pipette. But still after all this, we face difficulties of how to take precise reading from pipette.
Example-
1. Due to the concave water meniscus, until where to take the reading ?
2. Is it really important to take every ... |
How to get a precise reading from pipette? |
While studying about bonding there was one statement written that "pi bond can only be formed only in formation to sigma bond" as we know that in double bond there is 1 sigma bond and 1 pi bond but then one question arises: Why a pi bond is formed only when a sigma bond is formed? Is it possible to form a pi bond witho... |
Why are pi bonds is formed only when sigma bonds are formed? |
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