Question

For a reaction $\frac{1}{2}A\to 2B$, rate of disappearance of A is related to the rate of appearance of B by the expression:

• A. $\frac{-d\left[A\right]}{dt}=\frac{d\left[B\right]}{dt}$
• B. $\frac{-d\left[A\right]}{dt}=4\frac{d\left[B\right]}{dt}$
• C. $\frac{-d\left[A\right]}{dt}=\frac{1}{4}\frac{d\left[B\right]}{dt}$
• D. None of these

Answer 1

Answer: (C)

$\frac{-d\left[A\right]}{dt}=\frac{1}{4}\frac{d\left[B\right]}{dt}$

For the reaction $\frac{1}{2}A\to 2B$, rate of disappearance of A is related to rate of appearance of B by the expression:

$\frac{-2d\left[A\right]}{dt}=\frac{1}{2}\frac{d\left[B\right]}{dt}$

$\frac{-d\left[A\right]}{dt}=\frac{1}{4}\frac{d\left[B\right]}{dt}$

Hence, option C is correct.