(i) Write structures of different isomeric amines corresponding to the molecular formula, `C_(4)H_(11)N.`
ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?

Explanation

(I, ii) primary amines,
(a) `underset("Butanamine")(CH_(3)CH_(2)CH_(2)CH_(2)NH_(2))`
(b) `underset("Butan-2-amine")(CH_(3)CH_(2)-underset(NH_(2))underset(|)(C)H-CH_(3))`
(c) `underset("2-Methylpropanamine")(overset(3)(C)-overset(CH_(3))overset(|)(.^(2)C)H-overset(1)(C)H_(2))-NH_(2)`
(d) `underset("2-Methylpropan-2-amine")(CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-NH_(2))`
Secondary amines:
(e) `underset("N-Methylpropanamine")(CH_(3)CH_(2)CH_(2)-NH-CH_(3))`
(f) `underset("N-Methylpropan-2-amine")(overset(3)(C)H_(3)-overset(.^(1)CH_(3))overset(|)(.^(2)C)H-NH-CH_(3))`
(g) `underset("N-Ethylthanamine")(CH_(3)-CH_(2)-NH-CH_(2)CH_(3))`
Tertiary amines:
(h) `underset("N,N-Dimethylethanamine")(CH_(3)-overset(CH_(3))overset(|)(N)-CH_(2)CH_(3))`
(iii) Position isomers: (a) and (b), (e) and (f)
Chain isomers: (a) and (c), (a) and (d), (b) and (c), (b) and (d).
Metamers: (e) and (g), (f) and (g).
(iv) Functional isomers: All `1^(@)` amines are functional isomers of `2^(@) and 3^(@)` amines and vice-versa.