who can explain???

[xDent09]

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When talkin about melting and bioling points example for alcohols, so does it mean that when every b.p increases, m.p increases?

 

[DrReo]

When talkin about melting and bioling points example for alcohols, so does it mean that when every b.p increases, m.p increases?

boiling point: increases as chain length increases; decreases when the molecule branches

melthing point: increases as chain lenth increases; decrease with branching.

 

[Mstoothlady2012]

When you find atoms in the molecule that can hydrogen bond it will increase the boiling point. I haven't read anywhere that says same applies to melting point as well, but I have seen many examples where it applies to both melting point and boiling point...like you said alcohols.

 

[arpitpatel86]

do e- w/drawing groups have nething to do w/ bp mp or acidty at all?

 

[la brat]

boiling point: increases as chain length increases; decreases when the molecule branches

melthing point: increases as chain lenth increases; decrease with branching.

melting point does not necessarily decrease with branching. If the branching is symmetrical and approaches a crystalline structure, packing of the molecules is tighter, and therefore, the melting point increases. Neopentane is an example.

 

[userah]

meta directors increase acidity

 

[Zerconia2921]

When talkin about melting and bioling points example for alcohols, so does it mean that when every b.p increases, m.p increases?

If your talking about colligative properties which dosent matter what molecule it is but the amount of it in solution then yes the b. p increase and the m.p. increase. This is because the molality (moles of solute over kg of solvent increase directly) so if you were calculated the T(b) = kbm the molaity fraction will increase. This is the same for Tf but with a differnt Kf.
Your example with alcohols the intermolecular attractions in solution which are H-bonds will indeed make the boiling point increase and for m.p. I am not too sure maybe somone has a better explanation..