Q19 / 160 · AP EAMCET 2009 · Chemistry

How many ' $\mathrm{mL}$ ' of perhydrol is required to produce sufficient oxygen which can be used to completely convert $2 \mathrm{~L}$ of $\mathrm{SO}_2$ gas to $\mathrm{SO}_3$ gas?

  • Correct answer
    A
    10 mL
  • B
    5 mL
  • C
    20 mL
  • D
    30 mL

Solution

Perhydrol means $30 \%$ solution of $\mathrm{H}_2 \mathrm{O}_2$. $\mathrm{H}_2 \mathrm{O}_2$ decomposes as $2 \mathrm{H}_2 \mathrm{O}_2 \longrightarrow 2 \mathrm{H}_2 \mathrm{O}+\mathrm{O}_2$ Volume strength of $30 \% \mathrm{H}_2 \mathrm{O}_2$ solution is 100 that means $1 \mathrm{~mL}$ of this solution on decomposition gives $100 \mathrm{~mL}$ oxygen. $\begin{array}{lcc}\mathrm{SO}_2 & +\frac{1}{2} \mathrm{O}_2 \longrightarrow & \mathrm{SO}_3 \\ 1 \mathrm{~L} & \frac{1}{2} \mathrm{~L} & 1 \mathrm{~L} \\ 2 \mathrm{~L} & 1 \mathrm{~L} & 2 \mathrm{~L}\end{array}$ Since, $100 \mathrm{~mL}$ of oxygen is obtained by $=1 \mathrm{~mL} \text { of } \mathrm{H}_2 \mathrm{O}_2$ $\therefore 1000 \mathrm{~mL}$ of oxygen will be obtained by $\begin{aligned} & =\frac{1}{100} \times 1000 \mathrm{~mL} \text { of } \mathrm{H}_2 \mathrm{O}_2 \\ & =10 \mathrm{~mL} \text { of } \mathrm{H}_2 \mathrm{O}_2 \end{aligned}$

Hence, the correct answer is option: 'A'.

Relevant Questions