Question

In which of the following organic molecules might we expect hydrogen bonding to occur? benzoic acid (C6H5CO2H) acetone (2-propanone) N,N-dimethylacetamide [CH3CON(CH3)2, an amide formed from acetic acid and dimethylamine] methyl acetate, CH3CO2CH3

the last two options:

acetaldehyde (ethanal), CH3CHO

acetamide (CH3CONH2 an amide formed from acetic acid and ammonia)

Answer 1

We might expect hydrogen bonding to occur in benzoic acid and acetamide.

Explanation:

(a) Benzoic acid

The formula for benzoic acid is `"C"_6"H"_5"C(=O)OH"`.

Benzoic acid contains an `"OH"` group, so it should have hydrogen bonding,

(b) Acetone

The formula for acetone is `("CH"_3)_2"C=O"`. It contains no `"OH"` group, so there is no hydrogen bonding.

(c) N.N-Dimethylacetamide

The formula for N.N-dimethylacetamide is `"CH"_3"C(=O)N"("CH"_3)_2`. It contains no `"OH"` or `"NH"` group, so there is no hydrogen bonding.

(d) Methyl acetate

The formula for methyl acetate is `"CH"_3"C(=O)OCH"_3`. It contains no `"OH"` group, so there is no hydrogen bonding.

(e) Acetaldehyde

The formula for methyl acetate is `"CH"_3"C(=O)H"`. It contains no `"OH"` group, so there is no hydrogen bonding.

(f) Acetamide

The formula for acetamide is `"CH"_3"C(=O)NH"_2`. It contains two `"NH"` bonds, so there is hydrogen bonding.