Q23 / 160 · AP EAMCET 2023 (18 May Shift 2) · Chemistry
A reaction, $3 \mathrm{X}(\mathrm{g}) \rightarrow 2 \mathrm{Y}(\mathrm{g})+\mathrm{Z}(\mathrm{g})$ takes place in a closed vessel. What is the rate of formation of $Y$ (in $\mathrm{mol} \mathrm{L}^{-1}$ ) if the rate of disappearance of $\mathrm{X}$ is $7.2 \times 10^{-3} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~s}^{-1}$ ?
- A$3.6 \times 10^{-3}$
- Correct answerB$4.8 \times 10^{-3}$
- C$2.4 \times 10^{-3}$
- D$1.2 \times 10^{-3}$
Solution
$\begin{aligned} & \text { }-\frac{1}{3} \frac{\mathrm{d}[\mathrm{X}]}{\mathrm{dt}}=\frac{1}{2} \frac{\mathrm{d}[\mathrm{Y}]}{\mathrm{dt}}=\frac{\mathrm{d}[\mathrm{Z}]}{\mathrm{dt}} \\ & \Rightarrow \frac{\mathrm{d}[\mathrm{Y}]}{\mathrm{dt}}=\frac{2}{3} \frac{\mathrm{d}[\mathrm{X}]}{\mathrm{dt}}=\frac{2}{3} \times 7.2 \times 10^{-3} \\ & =4.8 \times 10^{-3} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~S}^{-1}\end{aligned}$
Hence, the correct answer is option: 'B'.