(a)(i) Structural Isomers of C\(_4\)H\(_4\)

(ii) (I)Tertiary(3°)alkanol.

(II) Primary (1°)alkanol.

(III) Secondary (2°) alkanol



(b)(i)

(I) CH\(_3\)CH\(_2\)COOK, H\(_2\)

(II) CH\(_3\)CH\(_2\)COOC\(_4\)H\(_9\) H\(_2\)O

(III) CH\(_3\)CH\(_2\)CH\(_2\)COOH

(ii) Major products in (b)(i) (1) — Potassuim propanoate (II) — Butyl propanoate (III) — Butanoic acid



(C)(i) % carbon by mass = 100 – 14.3 (l) = 85.7%

Ratio of atoms = \(\frac{C}{\frac{85.7}{12.0}}\) = 7.1415; \(\frac{H}{\frac{14.3}{1.0}}\) = 14.3

Divide by smaller number = \(\frac{7.1415}{7.1415}\) = 1; \(\frac{14.3015}{7.1415}\) = 2

Empirical Formular = CH\(_2\)



(i) 2.24dm\(^3\) = 7.0g of R

22.4dm\(^3\) = \(\frac{7.0}{2.24}\) x 22.4 = 70gmol\(^1\)

OR

Molar volume of gas = 22.4 dm\(^3\) at s.t.p 22.4

22.4 dm\(^3\) gas = 1 mole

22.4 dm\(^3\) = \(\frac{2.24}{22.4} \times 1\) = 0.1 mol

But numbers of moles = 0.1

Mr = \(\frac{7}{0.1}\) = 70gmol\(^1\)

Molecular formular = C\(_5\)H\(_{10}\)

(CH_2)n = 70

14n = 70

n = \(\frac{70}{4}\) = 5



(d) The occurence of / existence of / condition whereby compounds with the same molecular formula have different structural formulae.