Linked Questions
16 questions linked to/from Utility of Bent's Rule - What can Bent's rule explain that other qualitative considerations cannot?
47
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2
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Are the lone pairs in water equivalent?
I've read that the oxygen atom in water is $\mathrm{sp^2}$ hybridized, such that one of the oxygen lone pairs should be in an $\mathrm{sp^2}$ orbital and the other should be in a pure p atomic orbital....
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30
votes
4
answers
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Why are DCM and chloroform so resistant towards nucleophilic substitution?
In the book Organic Chemistry by J. Clayden, N. Greeves, S. Warren, and P. Wothers I found the following reasoning:
You may have wondered why it is that, while methyl chloride (chloromethane) is a ...
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28
votes
3
answers
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What is Y-aromaticity? Is the trinitromethanide anion aromatic?
The wikipedia article on trinitromethane claims that:
There is some evidence that the anion (which obeys the $4n+2$ Hückel rule) is aromatic.
Unfortunately the citation is behind a paywall so I ...
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7
votes
2
answers
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What is the molecular geometry of NHF₂?
I had to draw the molecular shape for $\ce{NHF2}$ as a Trigonal Planar like this
But when I check to make sure it was right, I came across a source saying
NHF2-difluoroammonia--tetrahedral, ...
13
votes
2
answers
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Are carbocations necessarily sp2 hybridized and trigonal planar?
My copy of Pearson's Organic Chemistry (7e), Morrison and Boyd, under the section "Reaction intermediates", accords a succinct description on the structure of carbocations:
The central $C$-atom (of ...
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19
votes
1
answer
16k
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What is the hybridization of the carbonyl oxygen in a carboxylic acid?
My professor sent out a review guide. One of the questions on this guide is
The carboxylic acid carbonyl oxygen is:
1. $\ce{sp^2}$
2. $\ce{sp^3}$
3. $\ce{H}$-bond donor
4. rapidly ...
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10
votes
3
answers
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Why the bond angle of PH3 is lesser that that of PF3?
We can explain why the bond angle of $\ce{NF3}$ (102°29') is lesser than $\ce{NH3}$ (107°48') by the VSEPR theory, since lone pair lone pair repulsion is greater than lone pair bond pair repulsion. ...
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11
votes
2
answers
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Is the phenyl cation or ethynylium more stable?
I recently gave an exam and I received an interesting question to which I believe the answer is wrong.
Given two compounds, a benzene molecule with carbocation at one of its constituting carbon atoms ...
- 221
11
votes
1
answer
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Why does SO2 have a larger bond angle than H2O, H2S, and NH3
So we have to find which of the follwing compounds has the smallest bond angle:
$\ce{H2O}$, $\ce{H2S}$, $\ce{NH3}$, $\ce{SO2}$.
So L $\propto \frac{1}{BA}$
where $L$ is the number of lone pairs and $...
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8
votes
3
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Why is the H−C−H bond angle in сhloromethane larger than 109.5°?
Symmetrical tetrahedral molecules (like $\ce{CH4}$) have a bond angle of $109.5$. Those with lone pairs in place of one atom (like $\ce{NH3}$) have bond angles less than $109.5$.
The standard ...
- 201
4
votes
4
answers
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What is the CNC bond angle in methyl isocyanate?
Methyl isocyanate, $\ce{HC3NCO}$, is a toxic liquid which is used in the manufacture of some pesticides. What is the approximate angle between the bonds formed by the nitrogen atom in a molecule of ...
- 51
6
votes
1
answer
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Comparison of C-Cl bond length in CH3Cl and CF3Cl
How can one compare the $\ce{C-Cl}$ bond lengths in chloromethane ($\ce{CH3Cl}$) and chlorotrifluoromethane ($\ce{CF3Cl}$)?
Bent's rule is also consistent with Gillespie's VSEPR model, and may ...
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3
votes
2
answers
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What are the bond angles in cyclohexane?
In the chair conformation of cyclohexane, what are the angles of the triangles defined by:
a carbon atom, an axial hydrogen bonded to it, and the midpoint of a vicinal C-C bond ?
a carbon atom, an ...
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5
votes
2
answers
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Comparing bond angles in carbonyl dichloride and carbonyl dibromide
Background
I was studying VSEPR and hybridization theory and one of the popular questions in many textbooks was comparison of bond angle of $\ce{NH3}$, $\ce{NF3}$ and $\ce{NCl3}$.
$\ce{NF3}$ had ...
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3
votes
1
answer
232
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Negative s - orbital chatacter
I am learning about how to calculate s-orbital character. While doing so, I came across a formula
$$\cos\theta = \frac{s}{s-1}.$$
For cycloproprane, I used $\theta = 60^\circ,$ and got $s = -1.$
How ...
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