Question

A mixture of formic acid and oxalic acid is heated with concentrated $H_2{SO}_4$. The gaseous product is passed into $KOH$ solution where the volume decreases by 1/6th. The molecular proportion of the organic acids, formic acids and oxalic acid in the mixture is ___.

• A. $4:1$
• B. $1:4$
• C. $1:2$
• D. $2:1$

Answer 1

Answer: (A)

$4:1$

$\underset{1-mole}{HCOOH}+H_{2}S{O}_4⟶\underset{1-mole}{CO}+H_{2}S{O}_4{H}_{2}Oxx$

$\underset{1-mole}{H_2{C}_2{O}_4}+H_{2}S{O}_4⟶\underset{1-mole}{CO}+\underset{1-mole}{C{O}_2}+H_{2}S{O}_4{H}_{2}Oyyy$

$KOH$ absorbs only $C{O}_2,$ Total moles of $C{O}_2+CO=x+2y$

$\therefore$ Ratio of volume absorbed by $KOH$ is,

$\frac{y}{x+2y}=\frac{1}{6}$

$4y=x$

$\therefore x:y=4:1$