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Top new questions this week:

Why is a C4 ring impossible?

I am admittedly not a chemist. I was playing with a molecule set recently and I created a ring molecule where I double-bonded four carbon molecules to each other in a ring. I was in my university's ...

user avatar asked by Jakob Lovern Score of 15
user avatar answered by Poutnik Score of 15

What does the 'S' stand for in base-centered cubic crystals and Bravais lattices?

The 'I' used for body-centered systems is for the German word Innenzentriert and the 'F' for face-centered is for Fl├Ąchenzentriert, also German but what about the 'S' for a, b, or c base-centered ...

crystal-structure terminology crystallography minerals  
user avatar asked by Kurt Hikes Score of 7
user avatar answered by AChem Score of 8

What's the relation between two symmetry groups, if one has all the symmetry of the other and some more?

Question: Consider two molecular symmetry groups, for example $C_s$ and $C_{2v}$. $C_s$ has one inversion plane, and two irreductible representations: the symmetric $A'$, and the antisymmetric $A''$. ...

terminology symmetry  
user avatar asked by Neinstein Score of 6
user avatar answered by orthocresol Score of 7

What results from the neutralization of copper citrate with Na2CO3

I found this question that describes PCB etching with citric acid. The answer to that question explains how hydrogen peroxide, salt, and citric acid can be used to ionize copper metal in water, which ...

inorganic-chemistry acid-base everyday-chemistry  
user avatar asked by KJ7LNW Score of 4
user avatar answered by Poutnik Score of 1

Looking for terminology for when a hygroscopic chemical gets moisture in it

Scenario: A jar of zinc chloride (which is very hygroscopic) is left on a shelf in a chemistry classroom for several years. You open it and it is hard. What is the word to describe that? It was ...

terminology teaching-lab  
user avatar asked by Jessica Sargent Score of 4
user avatar answered by AChem Score of 6

Copper plating surface color shifts from light to dark orange to black in less than 12 hours

We have been doing barrel-type copper plating on small parts, and all of a sudden there is an increase of copper plating discoloration after copper plating. The color shifts from bright orange (good) ...

user avatar asked by Kim Maric Score of 4
user avatar answered by Oscar Lanzi Score of 3

Comparison of acidic strength in organic compounds by assigning charges to rings

Generally we compare acidic strengths by comparing relative stability of negative charge formed by removal of acidic hydrogen. However I can't understand the following comparison The solution given ...

organic-chemistry aromaticity  
user avatar asked by hemant kumar Score of 3
user avatar answered by Sticklink Score of 0

Greatest hits from previous weeks:

Melting points and boiling points of primary alcohols do not follow the same trend

If one considers boiling points (in ┬░C) of primary alcohols, one finds the following: methanol: 65 ethanol: 79 1-propanol: 97 1-butanol: 117 1-pentanol: 138 This trend is due to Van der Waals forces ...

organic-chemistry physical-chemistry boiling-point melting-point  
user avatar asked by mannaia Score of 2
user avatar answered by Nicolau Saker Neto Score of 3

How do you explain pKa to non-professional?

Let's say we have substance $\ce{A}$, which is mixed with substance $\ce{B}$ to improve shelf-life because $\mathrm{p}K_\mathrm{a}$ of the substance $\ce{A}$ is $7.9$ and in mix the $\mathrm{pH}$ is $...

acid-base solubility  
user avatar asked by Ilan Score of 7
user avatar answered by jerepierre Score of 13

Reaction between NaOH and CO2

So I wanted to know what the reaction between sodium hydroxide and carbon dioxide can be, and upon research I got 2 answers. The first one is $$\ce{CO2 + NaOH(aq) -> NaHCO3(aq)}$$ and the second ...

inorganic-chemistry acid-base reaction-mechanism aqueous-solution  
user avatar asked by user510 Score of 6
user avatar answered by user213305 Score of 5

What's the difference between alpha-glucose and beta-glucose?

What's the difference between $\alpha$-D-glucose and $\beta$-D-glucose? Are they isomers? Or do they differ in their elemental composition?

stereochemistry isomers carbohydrates  
user avatar asked by a06e Score of 17
user avatar answered by Ben Norris Score of 29

Preparation of iodine solution

How to prepare $\mathrm{0.1M}$ $\ce{I_2}$ solution. I have found in books that it should be prepared in $\ce{KI}$ solution but none of them explains why? Please explain in detail not just the ...

user avatar asked by user3236187 Score of 6
user avatar answered by Yomen Atassi Score of 15

Difference between exothermic and exergonic

In High School I learned that an exothermic reactions releases energy, while an endothermic reaction needs energy to occur. Now I learned that there is a separate, somewhat similar classification ...

thermodynamics enthalpy free-energy  
user avatar asked by Martin J.H. Score of 30

What is "heating under reflux"?

When dealing with organic reactions, heating under reflux is often required, such as the oxidation of Toluene using acidified $\ce{KMnO4}$ and dilute $\ce{H2SO4}$ to Benzoic acid($\ce{C6H6O2})$ What ...

organic-chemistry heat  
user avatar asked by Huey Score of 13
user avatar answered by Huey Score of 21

Can you answer these questions?

Why the IUPAC naming of this compound is 6-hydroxycyclohex-2-en-1-one?

Should it not be 2hydroxycylohex-5-en-1-one? Functional groups are usually given more priority than double/triple bonds, except in cases of Nitro, halides, etc. Shouldn't the priority order be Ketone&...

organic-chemistry nomenclature  
user avatar asked by Avani Score of 1

Colored inorganic liquids: why is SCl2 red, and S2Cl2 orange?

Those do not involve d orbitals, so there is no crystal field theory or ligand theory. Do we have a name of study that only involves p orbitals? Since I think molecular theory is for all s p d f ...

inorganic-chemistry color liquids  
user avatar asked by Neal Conroy Score of 2

Which way is this coordination equilibrium likely to lie (entropic vs enthalpic factors)?

The question is asking where this aqueous equilibrium is likely to lie. My thought process is that, because Li+ is a smaller cation than Na+, with a greater charge density, upon displacement it will ...

user avatar asked by Bartholomew696969 Score of 1
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