The Periodic Table

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12:49 AM

Q: Determining number of unique hydrogens in lactupicrinal 1H NMR

I'm having trouble understanding which hydrogens are magnetically distinct in the following molecule (lactupicrinal): I've counted all the hydrogens (there are 20) and I know that hydrogens in a methyl group are all chemically the same (I think), but I don't know about the hydrogens in the et...

5 hours later…

Intellex

5:40 AM

@Jan: Is it advisable to start a bounty for the following question or "forget it" as advised by you?

Q: Why is back bonding not possible in sulfur dichloride?

In Concise Inorganic Chemistry by JD Lee (4th edition; adapted by Sudarshan Guha), page 76 under the topic "Back Bonding" it is given: For $\ce{SCl2}$ the bond angle is 102° since the lone pair of $\ce{S}$ or $\ce{Cl}$ atoms need not be delocalised due to the availability of vacant d orbitals...

inorganic-chemistry bond

Jan

6:29 AM

@Intellex Whether you want to offer your rep as a bounty is up to you. It might attract answers that help you; it might not.

Hot nitric acid (HNQ)

Q: Graph Laplacian based on Hückel theory

While studying graphs and graph Laplacians from "Laplacian eigenvectors of graphs: Perron-Frobenius and Faber-Krahn type theorems.", I encountered a type of graph Laplacians that rise from quantum chemistry. This matrix is consists of off-diagonal elements called resonance integrals and diagonal ...

quantum-chemistry computational-chemistry

Intellex

7:04 AM

@Jan Thanks for your reply :)

Who is this Hot Nitric Acid? Is that a robot?

Jan

Yes.

2 hours later…

Jan

9:07 AM

I like lab days if my only reactions are 1) pouring sulphuric acid on a compound and 2) adding NBS, dissolving in DCM and refluxing (probably overnight).

7 hours later…

Hot nitric acid (HNQ)

4:28 PM

Q: What is the interaction between dissolved ions of opposite valence in a solution at rest?

NaCl is dissolved in water. Ions sodium and chloride are sufficiently free from each other so that they may occupy different regions of the solution after an active transport process through a membrane, or a mere electric field is in place. They still act upon each other, and a membrane voltage ...

physical-chemistry electrochemistry aqueous-solution solutions

M.A.R.

4:41 PM

@Intellex It's a chemist joke because hot nitric acid = HNQ = Hot Network Questions HAHA ZOMG HEEEHEHEHEHEH sheds tear of joy Anyway, we can have chatbots and name them and tell them what to post. In this case, Chem questions that make it to the HNQ.

Jan

Also do we still have that other bot?

M.A.R.

4:57 PM

@Jan Meh, it stopped working when you were still here

Jan

@M.A.R. I established recently that I’m old, do you think I still remember?

M.A.R.

@Jan actually, older people remember exactly the older things

Our generation has forgotten yesterday's lunch amid taking a selfie beside today's.

Jan

@M.A.R. Yes but that was still recent, I’ve only been gone for like a week, right?