Nick T
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4 answers
29 votes
9k views
Is activated carbon classified as organic or inorganic?
Accepted answer
25 votes

While nomenclature is of particular interest to organic chemists to specify an exact compound, the classification of X into broad category Y or Z isn't a precise science, and not really of practical ...

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3 answers
41 votes
14k views
Why do impurities lower the melting point of an isolated substance?
19 votes

Thermodynamically, you're considering the chemical potentials ($\mu$) of the liquid and solid(s), specifically the temperature where they're equal. In a mixture, the potential is lower as the ...

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1 answers
4 votes
552 views
How does the composition of ice differ from that of water in a partly frozen solution?
3 votes

It sounds like you're talking about freezing-point depression. If the solid component of a system is pure (oft assumed so; crystals are good at excluding impurities), the equilibrium is shifted ...

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1 answers
3 votes
2k views
Why do buffers need to be composed of equal amounts of the acid and salt?
Accepted answer
3 votes

They don't need to be comprised of equal amounts. However, when you are near the 50:50 point, the buffer is "unbiased" (a contrived term), and it can equally accommodate assaults to its pH going in ...

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4 answers
6 votes
2k views
Is oxygen necessary for burning?
1 votes

"Burning" is a rapid exothermic oxidation reaction, so you need some sort of oxidizer. Gaseous oxygen serves quite well, as well as oxygen bound up in various solids like nitrates (e.g. potassium ...

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