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Unanswered Questions

1,030 questions with no upvoted or accepted answers
14 votes
1 answer
4k views

Inter electronic repulsion in s and d orbitals

This was written in a lecture slide: Two electrons present in the same d-orbital repel each other more strongly than do two electrons in the same s-orbital. Why is there a difference in the amount ...
10 votes
1 answer
328 views

Why are IUPAC's definitions of exo- and endothermic disconnected from the direction of heat flow?

I'm wondering if anyone can provide a rationale for IUPAC's definitions of exothermic and endothermic since they disconnect these terms from the direction of heat flow. Specifically, here are IUPAC's ...
8 votes
0 answers
392 views

What exactly is an "electron-sponge"?

What exactly an "electron-sponge" [behavior/action/property/system] nickname is, and what makes a material an "electron-sponge" (preferably, quantitatively)? From what I found, it's typically a ...
8 votes
0 answers
102 views

Removal of nickel plating on MgB2 without damaging the boride?

I need to remove a nickel plating of a MgB2 wire without causing damage to the MgB2. I felt that electrolysis is the best method but I do not know what electrolyte to use for this. I also need to coat ...
8 votes
1 answer
307 views

Are there bonds which share single electron?

Are there bonds which share single electron? During chemical bonding, I asked our teacher why there are only 2 electrons shared in a bond. He said that because it's that one orbital can accommodate ...
7 votes
0 answers
101 views

Why do nuclei move considerably slower than electrons

I've been trying to learn quantum chemistry at an introductionary level. While reading I've found out that the Born-Oppenheimer approximation seems to be the reason for the basic and crucial model of ...
7 votes
0 answers
183 views

Why does entropy increase in reactions that make more molecules?

I used to understand this (more molecules ⇒ more degrees of freedom), but do no longer, because the total number of atoms is conserved, so translational d.o.f. should just be turned into internal d.o....
7 votes
0 answers
349 views

Electron promotion in hybridisation: A misconception

Recently, I read through a short article on Nature Chemistry, written by Michelle Francl, titled "Talking to Pauling's ghost". The article talks about how electron promotion was never something that ...
7 votes
0 answers
516 views

Does phosphoric acid remove stainless steel electropolished layer?

Electropolished stainless steel has a high corrosion resistance due to the oxide film that is created during electropolishing. The film mainly consist of chromium(III) oxide. Phosphoric acid is ...
6 votes
0 answers
82 views

Do "pseudo Van der Waals" gases exist?

In college, when deriving the Langmuir isotherm for gas-solid adsorption, the professor proposed a modified version of the Van der Waals state equation, what he called the "pseudo Van der Waals ...
6 votes
0 answers
135 views

Correct Definition of Absolute Electrode Potential

I thought absolute electrode potential is Galvani potential difference at the interface. However, it is given by following equation in John Bockris - Modern Electrochemistry (Ref.1): $$ E^M \mathrm{(...
6 votes
0 answers
206 views

Why is the reverse aldol cleavage of fructose 1,6-bisphosphate highly endergonic under standard conditions?

I have another question similar to this one. I just don't have intuition for why reactions are thermodynamically favorable or unfavorable and I'd like to build it. This time I'd like to ask about ...
6 votes
1 answer
197 views

Understanding elementary rate laws from a probability stand point

I am learning about chemical kinetics and dynamics and as I understand for a general chemical reaction $$\ce{aA + bB -> cC + dD} $$ whose reaction rate, r, can be described by an elementary rate ...
6 votes
0 answers
614 views

Thermophysical properties of liquid Galden LS 230 between 25 °C and 230 °C

I'm looking for thermophysical properties of Galden LS 230, a liquid polymer (PFPE) produced by Solvay (https://www.solvay.com/en/markets-and-products/featured-products/Galden.html) at temperatures ...
6 votes
0 answers
207 views

I found transition states (TS), but calculations aren't supported by experiment. Do I look for more TSs or somewhere else?

I'm using Gaussian to investigate a catalyst system. Experimental evidence showed that one of three analogues (R = phenyl, Ph), yielded a benzosultam when treated with 2,4,6-...

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