Question

The units of rate and rate constant for a certain reaction are same. The order of reaction is:

• A. $1$
• B. $0$
• C. $2$
• D. $3$

Answer 1

The correct option is B $0$

$\text{Unit of rate of the reaction}={\text{mol L}}^{-1}{\text{s}}^{-1}$

$\text{For zero-order, the unit of the rate constant}={\text{mol L}}^{-1}{\text{s}}^{-1}$
$\text{For first-order, the unit of the rate constant}={\text{s}}^{-1}$
$\text{For second-order, the unit of the rate constant}={\text{mol}}^{-1}{\text{L s}}^{-1}$
$\text{For third-order, unit of the rate constant}={\text{mol}}^{-2}{\text{L}}^2{\text{s}}^{-1}$

Hence, for a zero order reaction, the units of rate and rate constant will be same.
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