Linked Questions

89
votes
2answers
35k views

What is Bent's rule?

I'm all bent out of shape trying to figure out what Bent's rule means. I have several formulations of it, and the most common formulation is also the hardest to understand. Atomic s character ...
47
votes
3answers
8k views

Is buckminsterfullerene aromatic?

According to Wikipedia, The $\ce{C60}$ molecule is extremely stable,[26] withstanding high temperatures and high pressures. The exposed surface of the structure can selectively react with other ...
13
votes
3answers
6k views

Is the S–O bond strength in sulfur trioxide or sulfite anion larger?

Can you please explain the difference between the bond enthalpies in sulfurtrioxide $\ce{SO3}$ and the sulfite anion $\ce{SO3^{2-}}$?
14
votes
3answers
29k views

Why is the bond order in the SO₃ molecule 1.33 and not 2?

$\ce{SO3}$ molecule has three double bonded oxygen to the central sulfur atom. Sulfur has $\ce{sp^2}$ hybridization and it has 6 outer electrons which make the bonds with the oxygen. So shouldn't ...
15
votes
1answer
5k views

Utility of Bent's Rule - What can Bent's rule explain that other qualitative considerations cannot?

Does Bent's rule have any utility? I got a vehement earful for "NO." Points raised by my professor: Coulombic considerations can be used to rationalize bond angles, strengths, and lengths without ...
13
votes
1answer
9k views

Delocalization of π-electrons in nitrate ion

Benzene and nitrate ion are given in my textbook as examples for the delocalization of π-electrons. Benzene, due to symmetry of its resonating structures, is simple enough. We assume that σ-electrons ...
8
votes
2answers
1k views

Can a cyclic amine form an amide?

This is a question from the Cambridge International Examinations October/November 2017 (pdf from papers.gceguide.com, pdf via the Wayback Machine). I need to understand why the secondary amine in the ...
4
votes
1answer
12k views

Backbonding in molecules like BF3

Can anyone please briefly explain to me the concept of backbonding along with necessary conditions for backbonding with some example? As I understand, backbonding is a donation of electron from ...
9
votes
2answers
6k views

Why isn't the side chain of arginine totally protonated at low pH?

I was wondering why arginine cannot be protonated at $\mathrm{pH\ 0}$ on all the $\ce{N}$ atoms in the side chain, as they all have a free electron pair. As this image shows, it can only be protonated ...
16
votes
1answer
2k views

Why are tertiary carbocations so stable?

Today our lecturer provided this data to illustrate the relative stability of carbocations. \begin{array}{|c|c|c|c|c|} \hline \text{Substrate} & \ce{t-BuBr} & \ce{i-PrBr} & \ce{EtBr} &...
19
votes
1answer
962 views

What is three dimensional aromaticity?

I have recently come across a statement which states: The relative stability of the 1,3-dehydro-5,7-adamantanediyl dication is ascribed to its three-dimensional aromaticity. [1] My ...
2
votes
0answers
295 views

Why isn't trinitramide planar?

The lewis structure of trinitramide has four major resonance structures, whereby the lone pairs of the central nitrogen can resonate with the nitro groups. This seems to indicate that each of the ...
2
votes
0answers
214 views

How will Back-Bonding affect molecular geometry?

While going through a textbook, I came across the following line: $\ce{R3C-}$ is pyramidal while $\ce{(CN)3C-}$ is planar due to lack of back bonding from the lone pair of carbon atom into the $\pi^...