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1500 questions
15
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2 answers
Why is HCl not considered to have hydrogen bonding?
A molecule that has hydrogen bonding usually follows these two premises.
1.) There is a hydrogen atom involved
2.) Hydrogen must be bonded to a highly electronegative element which are nitrogen ($\ce{N}$), fluorine ($\ce{F}$) and oxygen…
Luis Averhoff
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Why is it the middle ring of anthracene which reacts in a Diels–Alder?
I'm wondering why maleic anhydride adds to the middle cycle of anthracene, and not the outer two.
I would have expected that a Diels–Alder with the outer ring would be better, because I expected a naphtalene part to be lower in energy than two…
laminin
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15
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What chemical characteristics give types of steel their properties?
I am a mechanical engineer, and just like everyone else I had classes on the crystal structure of metals, phase diagrams, and the various heat treatments.
However, even after diving back into that recently and researching online, I can't make sense…
Mister Mystère
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How to explain the dipole moment anomaly of methyl fluoride and methyl chloride with respect to their hydracids?
I was checking dipole moment orders, and came across a very peculiar result:
Methyl fluoride $(\ce{CH3F})$ has lesser dipole moment than methyl chloride ($\ce{CH3Cl}$), but hydrofluoric acid ($\ce{HF}$) has more dipole moment than hydrochloric acid…
Rajat Jain
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15
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What's so special about chelation?
There is another closely related post here , and I've also read the referenced wiki article including applications of chelation, but I still don't see what's so special about chelation. I understand the structure of the bond - the 'capturing' of a…
docscience
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15
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1 answer
Why does copper precipitate out as a pink solid?
When copper is precipitated out of a solution e.g from CuI, why does it appear pink instead of copper-coloured? Are there other situations where copper appears pink in solid form?
Naim Sen
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15
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How does chromium help stainless steel prevent rusting?
Various sources (such as this one) say that stainless steel is stainless because a passivation layer of an oxide is formed, but I haven't found details on why chromium helps create this passivation layer. I can think of a couple…
user1704042
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How does composition of air affect vapor saturation limit?
Suppose we hold temperature, pressure, and gas composition (say, a standard atmosphere) constant. Then we know that if we allow the water content of the air to vary it can range between 0 and some saturation limit S g/L.
How does that saturation…
feetwet
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15
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3 answers
Why is the bond order in the SO₃ molecule 1.33 and not 2?
$\ce{SO3}$ molecule has three double bonded oxygen to the central sulfur atom.
Sulfur has $\ce{sp^2}$ hybridization and it has 6 outer electrons which make the bonds with the oxygen.
So shouldn't the bond order be 2?
paul
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Can recent developments improve the total synthesis of B-12?
The total synthesis of vitamin B-12 by Robert Burns Woodward and Albert Eschenmoser, is over 30 years old. At its time, it was considered a landmark in the field.
With current developments (e.g. olefin metathesis, palladium catalysis, etc.) is it…
PKG
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Software for viewing a structure and altering bond angles
Does anyone know of any good software that would allow me to view the structure of a compound while also allowing me to change the bond angles in the structure (and give me numeric values for those angles)?
I'm looking for something freely…
Melanie Shebel
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15
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4 answers
Why does alcohol crack acrylic (plexiglass)?
I have seen videos and discussions about alcohol cracking acrylic, and waterblock manufacturers reminding users to not use alcohol in cooling systems with plexiglass acrylic, but why is this so?
The question proposed as duplicate only asked for the…
dennis97519
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1 answer
Why do some element symbols contain a single letter while others contain two letters?
As the title says, why do some element symbols contain a single letter while others contain two letters?
Endy Sun
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15
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1 answer
What is the difference between the units 'torr' and 'mm of Hg'?
According to present definition torr and mm of Hg differ though slightly.
I am still confused over it. Can someone write an explicit answer differentiating between them and the reason for differentiation as earlier they were considered same. The…
DSinghvi
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Derivation of formula for the degree of unsaturation
Degree of Unsaturation (DU) of an organic compound tells us about the total number of $\pi$ bonds (both double bonds and triple bonds) and number of rings/cyclic chains in the compound.
Degree of unsaturation forms an integral part of the four tools…
Aditya Sriram
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