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What causes the lowering of vapour pressure in volatile/nonvolatile solvent mixtures?
"Based on Figure 13.18, you might think that the reason volatile solvent molecules in a solution are less likely to escape to the gas phase, compared to the pure solvent, is that the solute molecules are physically blocking the solvent molecules…
Leponzo
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Why does superglue ignite cotton?
Cotton is mostly cellulose, a plant saccharide. Superglue refers to a class of cyanoacrylates. What is it about the two that causes ignition?
I'd imagine that the cellulose in cotton is in its linear form and not in its ring form since the…
Dissenter
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Fireplace window: Can one influence how fast soot is building up?
I'm sorry for such a stupid question, but after googling for half an hour I know two things
There are at least a zillion pages, blog-posts and articles about how to keep your fireplace window clean or how to clean it.
There is not a single page…
halirutan
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Is hydrogen bonding generally defined to include only three period two elements?
Traditionally, hydrogen bonding has been defined to only include interactions between a positively polarized hydrogen and three period-two elements: nitrogen, oxygen, and fluorine.
Why was this definition proposed? A common question is why can't…
Dissenter
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Why are lactones more acidic than esters?
Lactones ($\mathrm pK_\mathrm a \sim 25$) tend to be more acidic than esters ($\mathrm pK_\mathrm a \sim 30$). I know that the lactone is fixed in a (E)-conformation, due to the ring:
and that in normal esters, the (Z)-conformer is favoured based…
RedPen
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Why is proton transfer so fast?
Why is proton transfer always kinetically favored? In other words, why are Brønsted acid-base reactions so quick?
Is it because protons are generally unhindered, sterically? This seems plausible; consider an alcohol. The proton isn't blocked by any…
Dissenter
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How to solidify sand
I'm doing a research project where we analyzing the structure of sand after a certain process. To get a better idea of the internal structure of the sand, we use different colors to visualize the movement of the particles. However we can't actually…
Ortix92
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Evidence of orbitals?
How do we know that there are different types of orbitals? For example, what evidence is there for the existence of $\mathrm{p}$ orbitals instead of there being multiple $\mathrm{s}$ orbitals (for example, why isn't the electronic configuration of…
Zubair
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Toxicity of a sheet of lead?
I just went camping and someone brought a game from Australia. There was a wooden box with the top made of a thin, soft sheet of lead with a hole in it. The participants then throw coins at the box, and getting the coin inside gives some points,…
Mads Skjern
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Can in any case the faster step of the reaction be rate determining?
I found a sentence in book which states the reverse step of this reaction ( I forgot what was it!) has the faster step as rate determining .
Even Rate determining step-Wikipedia states:
In chemical kinetics, the rate (or velocity) of a reaction…
DSinghvi
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Why is carbonic acid often ignored?
Water (distilled or not) picks up CO2 from the atmosphere, some of which dissolves to form carbonic acid (H2CO3), lowering the pH by a point or two.
From that it seems like carbonic acid would be the bane of every chemists' existence, yet (in my…
Jason C
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Why is formic acid a stronger acid than acetic acid?
I am told that because the methyl group is electron donating in the conjugate base of acetic acid, this destabilizes the conjugate base by exacerbating the existing negative formal charge on the deprotonated oxygen, while in formic acid the electron…
Dissenter
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Turn lead into gold via radioactive decay
I was looking at the isotope's table and noticed that one of lead's isotopes can actually turn into stable gold through the following mechanism:
$$\ce{_{82}^{197}Pb -> _{81}^{197}Tl -> _{80}^{197}Hg -> _{79}^{197}Au}$$
I know (or at least guess)…
Hippalectryon
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Can a multi-species system oscillate around equilibrium?
In reading about chemical oscillations such as those that occur in the Belousov–Zhabotinsky reaction (BZ), it's often reported that these reactions were initially not taken seriously, because of a result that a homogeneous system cannot oscillate…
N. Virgo
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Why is magic acid a superacid?
The above is a representation of magic acid. The left part is the acid; the right part is the solvent. Why would this combination make for a particularly good acid?
The left part looks like a sulfuric acid derivative, except one of the oxygens has…
Dissenter
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