Ncert Exercises & Solutions

4.6: Time required to decompose SO2Cl2 to half of its initial amount is 60 minutes. If the decomposition is a first order reaction, calculate the rate constant of the reaction.

We know that for a 1st order reaction,

$t_{1 / 2} = \frac{0.693}{K}$
$I t i s g i v e n t h a t t_{1 / 2} = 60 m i n$
$∴ K = \frac{0.693}{t_{1 / 2}}$
$= 0.693$
$60$
$= 0.01155 m i n^{- 1}$
$= 1.155 m i n^{- 1}$
$o r K = 1.925 \times 10^{- 4} s^{- 1}$