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17
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2 answers
Emergency shower for nitric acid spills
Disclaimer: I'm asking this because I am curious. Not because I'm actually handling nitric acid.
In another answer I was reading, the poster mentioned that if you spill nitric acid, you shouldn't pour water on anything but a small spill, because it…
Patrick M
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17
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1 answer
What gives fresh milk a yellow tinge?
Every now and then, when I pop over to my grandparents' house, they make sure to give me a glass (or two) full of fresh milk (or "whole milk" if you will) and then proceed to pamper me for the rest of the day.
Now, it suddenly struck me that the…
paracetamol
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17
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1 answer
Stoichiometric defects in silver bromide
Stoichiometric defects (Schottky and Frenkel defects) in ionic crystals are formed due to irregularities in the ionic arrangement which maintain the stoichiometry and electroneutrality of the solid. It is known that $\ce{AgBr}$ shows both Frenkel…
stochastic13
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17
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1 answer
Why is 1H-borepine aromatic?
For a compound to be aromatic, each atom in the ring must be a part of conjugation. Boron here has no lone pair, so how can 1H-borepine be aromatic as I was told by someone?
Arishta
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17
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2 answers
What makes heat resistant proteins heat resistant?
We were doing the chapter Biomolecules in class the other day, and a doubt popped up once we reached the section on proteins.
We were taught that the stuff that keeps proteins together are: Ionic bonds (not always), Covalent bonds (peptide bonds and…
paracetamol
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17
votes
3 answers
Portable library to render 2D structural formulas as vector graphics from SMILES or InChI
For a web-based project, I am looking for a piece of software to create a 2D vector graphics structural formula from a textual structure encoding scheme such as SMILES or InChI, running on the server or client, and callable via some kind of API.
I’m…
Niels Heidenreich
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17
votes
1 answer
Why does paper turn yellow over time?
Yesterday I saw a bill of some book which I bought 6 months back. Then this question struck my mind: "Why does paper turn yellow over time"?
I remember my teacher saying some organic compound was used to make paper white. And this effect is reversed…
Vishnu JK
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17
votes
2 answers
How are the atomic orbitals for multi electron atoms obtained?
The problem with Schrödinger's equation is that it isn't exactly solvable for multi-electron species. In the past, atomic orbitals were used to construct a solution for molecules (LCAO). My question is, how were the multi electron atomic orbitals…
CoffeeIsLife
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17
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2 answers
Why is nitric acid such a strong oxidizing agent?
In my teaching-lab experiments I've seen that nitric acid solutions are able to facilitate the dissolution of metals such as silver, even though they are more active than hydrogen. Does anyone know why nitric acid is so special? Why is it such a…
a10y
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17
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Does the term 'Cation' always refer to a positively charged particle?
From what I was taught in middle school, cations are those ions that move towards the cathode, likewise anions are those ions which move towards the anode.
I didn't have issues with this back then, since all we studied were electrolytic cells. But…
paracetamol
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17
votes
2 answers
Which platonic solids have been built as carbon skeletons?
There are 5 platonic solids: the tetrahedron, the octahedron, the cube, the dodecahedron and the icosahedron.
How many of these have been realised as carbon skeletons by chemical synthesis?
matt_black
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17
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2 answers
What is the correct way to illustrate a bond to something irrelevant in a structural formula?
You can probably tell I'm not really a chemist (hi from physics!), but I've suddenly found myself having to draw some structural formulae, hence the stupid question.
I've drawn a diagram of the four DNA bases:
I don't care what they're attached to,…
georgewatson
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17
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3 answers
Won't the net effect of a catalyst be zero if it creates a new path with lower activation energy?
A catalyst will provide a new path with a lower activation energy (Figure 1). Won't this mean the forward and backward reactions will both speed up (as they both have a lower activation energy path to take)?
So then what is the point of using a…
K-Feldspar
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17
votes
2 answers
What utility does the tau bond model of orbital overlap have?
In his book on molecular orbital theory, Molecular Orbitals and Organic Chemical Reactions, Ian Fleming notes that Pauling formulated an early alternative model to Hückel theory for explaining the bonding of simple conjugated polyenes. Evidently,…
Greg E.
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17
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2 answers
What do these labels for molecular electronic states mean?
What do these symbols mean in excited states?
$${}^2\!A_2,{}^2\!B_1,{}^4\!A''$$
I am confused with these representations, found in the abstract of this paper. I think it is kind of a representation of electronic excited states. The left superscript…
Chao Song
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