Question

For the following homogeneous reaction, the unit of rate constant is: $A+B \xrightarrow{k}C$

• A. $ mol^{-1}L\,s^{-1}$
• B. $s^{-1}$
• C. $ s $
• D. $s^{-1}mol\,L^{-1}$

Answer 1

Answer: (A)

For the homogenous gaseous reaction,
$A+B \xrightarrow{k}C$, the rate law is
$\frac{d x}{d t} =k[A][B]$
or $k =\frac{d x}{d t \times[A][B]}$
$=\frac{mol\, L^{-1}}{\text { time } \times mol\, L^{-1} \times mol\, L^{-1}}$
or unit of rate constant k is $mol ^{-1}\, L\, time^{-1}$ or $mol^{-1}\,L\,s^{-1}$