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A drop of water in a tin of sugar: Which one's the solvent, the sugar or the water?
The other day, when we were dealing with the chapter Solutions, our teacher asked us this:
If I add a drop of water, to a tin full of sugar (without mixing it in), what's the solvent here? The water or the sugar?
Naturally we were taken aback by…
paracetamol
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Stability of alkenes tri>di>mono, but how to explain tetra
When we tell students about the formation of alkenes (by elimination for example), we often tell them that reactions will favour the thermodynamically favourable most substituted alkene. Zaistev's rule empirically described this:
"The alkene formed…
NotEvans.
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Do ligands with a positive charge exist?
Are there positively charged ligands which can bind to a central metal atom to form coordination compounds?
My thoughts:
I know that ligands are Lewis bases which donate a pair of electrons, and the central metal atom is usually a Lewis…
Rajath Radhakrishnan
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Why is the endo product the major product in a Diels-Alder reaction?
I understand that the endo product is, at least in all cases in my textbook, the major product in a Diels-Alder reaction. However, I don't understand why this is the case.
The explanation in my textbook says that the endo product allows for more…
user1
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Mechanistic Explanation of Circular Dichroism
I'm wondering if someone can give me a physically motivated reason for why chiral molecules interact with left and right circularly polarized light (LCP) (RCP) differently. Particularly, a quantum mechanical view of what's happening here.
I…
jheindel
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22
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3 answers
What is a virtual state?
In talking about Raman spectroscopy, one finds the Stokes line is simply the difference between the energy of an incoming photon and an emitted photon. This energy corresponds to a vibrational transition in terms of energy. Yet, the light sent at…
jheindel
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22
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1 answer
Migratory aptitude in Baeyer-Villiger reaction
In short, I do not understand how or why the migratory aptitude is as listed in every textbook I've read.
Firstly, they talk about a positive charge being built up that is stabilised by the movement of the most substituted group.
I cannot fathom…
Ari Ben Canaan
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How can I safely handle a concentrated (fuming) nitric acid spill?
I will shortly be using $90~\%$ or higher concentration nitric acid in a home environment for the purpose of decapping ICs. I understand the corrosive dangers of nitric acid, and most of the important dangers of its reactivity (e.g. exothermic with…
Polynomial
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Does anyone know what this piece of glassware is?
I recently found this piece of lab glass with a jacket and spout. It says eubilicmeter but I cannot find any information about it online and I do not know what it is supposed to do. It is hollow in the middle, sort of bell shaped. What is its name…
Chad
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f-electrons in chemistry of heavy transition metals
In one lecture at a recent MCR-X conference I was puzzled by a side-note "f-hole is critical to describe DoS of $\ce{IrO2}$ correctly." The context was DFT periodic plane-wave calculations with pseudization of the core electrons.
This implies that…
permeakra
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22
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3 answers
Pi electron stacking, how does it work?
I've come across the term base-pair stacking (with reference to B-DNA) in my school text book, and I had posted a question in that regard on Bio.SE.
I've also seen a similar (albeit brief) version of my question on Chem.SE.
I looked up the term…
paracetamol
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22
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3 answers
Can a chemical reaction have two balanced equations?
I was recently studying Xenon compounds and read this reaction:
$$\ce{6XeF4 + 12H2O -> 4Xe + 2XeO3 + 24HF + 3O2}$$
However this reaction can also be written as the following:
$$\ce{4XeF4 + 8H2O → 2Xe + 2XeO3 + 16HF + O2}$$
Now both of these are…
user34209
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4 answers
Acidity order of nitrophenols
As in other posts I have seen and learnt that, if one is given four compounds, namely para-nitrophenol, ortho-nitrophenol, meta-nitrophenol and phenol and is told to arrange them in order of acidity, then one has to take into account the $\text{-R}$…
Aneek
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Molecular Imaging - Any surprises to be had?
Molecular imaging, using STM and AFM technologies, appear so far to visually prove most of what we already know about chemical structures, such as VSEPR theory. For instance, here are the ideal structures and AFM of a couple of cyclization…
KeithS
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DFT Code for Atoms : Sources
Some time ago I implemented the restricted and unrestricted Hartree-Fock methods. I had a lot of fun and I learned a lot. It goes without saying that Szabo and Ostlund's book "Modern Quantum Chemistry" has been fundamental to achieve a working…
user23061