Q71 / 200 · NEET 2002 · Chemistry
$3 \mathrm{~A} \rightarrow 2 \mathrm{~B}$, then the rate of reaction $\frac{+d[\mathrm{~B}]}{d t}$ is equal to:
- A$-\frac{3}{2} \frac{d[\mathrm{~A}]}{d t}$
- Correct answerB$-\frac{2}{3} \frac{d[\mathrm{~A}]}{d t}$
- C$-\frac{1}{2} \frac{d[\mathrm{~A}]}{d t}$
- D$2 \frac{d[A]}{d t}$
Solution
For the reaction,
$\begin{gathered}
3 \mathrm{~A} \rightarrow 2 \mathrm{~B} \\
\text { Rate }=-\frac{1}{3} \frac{d[\mathrm{~A}]}{d t}=+\frac{1}{2} \frac{d[\mathrm{~B}]}{d t} \\
\therefore+\frac{d[\mathrm{~B}]}{d t}=-\frac{2}{3} \frac{d[\mathrm{~A}]}{d t}
\end{gathered}$
Hence, the correct answer is option: 'B'.