Question

For the following reaction:-
$xA\to yB$
$\log \frac{-d(A)}{dt}=\log \frac{d(B)}{dt}+0.3$
What is the ratio $x$ : $y$ ?

• A. 3 : 1
• B. 1 : 3
• C. 2 : 1
• D. 1 : 2

Answer 1

Answer: (C)

$xA\to yB$

Rate of reaction $=-\frac{1}{x}\frac{d(A)}{dt}=+\frac{1}{y}\frac{d(B)}{dt}$

$=-\frac{d(A)}{dt}=\frac{x}{y}\frac{d(B)}{dt}$

Taking log on both sides

$\log -\frac{d(A)}{dt}=\log \left(\frac{x}{y}\frac{d(B)}{dt}\right)$

$\log -\frac{d(A)}{dt}=\log \frac{x}{y}+\log \frac{d(B)}{dt}$

$\log \frac{x}{y}=0.3$

$\frac{x}{Y}=2$