Question

Identify A, B, C, D and E?

Answer 1

A, B, C, D and E are acetylene, acetaldehyde, acetic acid, acetyl chloride and ethyl acetate respectively.

Acetylene on treatment with sulphuric acid in the presence of HgSO${}_4$
yields acetaldehyde with molecular formula C${}_2$H${}_4$O.
$H-C\equiv C-H\underset{H_{2}S{O}_4}{\overset{HgS{O}_4}{\to }}C{H}_{3}CHO$
Acetaldehyde on oxidation with acidified potassium dichromate yields acetic acid
$C{H}_{3}CHO\stackrel{\text{acidified}{K}_{2}C{r}_2{O}_7}{\to }C{H}_{3}COOH$
Acetic acid gives effervescence with sodium bicarbonate.
$C{H}_{3}COOH+NaHC{O}_3\to C{H}_{3}COONa+H_{2}O+C{O}_2\uparrow$
Acetic acid when treated with SOCl${}_2$ gives acetyl chloride.
$C{H}_{3}COOH+SOC{l}_2\to C{H}_{3}COCl+S{O}_2\uparrow +HCl\uparrow$
When acetyl chloride reacts with ethanol it gives a sweet smelling liquid ethyl acetate.
$C{H}_{3}COCl+C_2{H}_{5}OH\to C{H}_{3}COO{C}_2{H}_5+HCl$
Ethyl acetate is also formed when acetic acid reacts with ethanol in the presence of conc. H${}_2$SO${}_4$.
$C{H}_{3}COOH+C_2{H}_{5}OH\stackrel{conc.H_{2}S{O}_4}{\to }C{H}_{3}COO{C}_2{H}_5+H_{2}O$

A $\to$ Acetylene, B $\to$ Acetaldehyde, C $\to$ Acetic acid, D $\to$ Acetyl chloride, E $\to$ Ethyl acetate.