Question

Complete the following statement by selecting the correct alternative from the choices given:
For a first order reaction the rate constant for decomposition of $N_2{O}_5$ is $6\times {10}^{-4}{sec}^{-1}$. The half-life period for the decomposition in seconds is:

• A. $11.55$
• B. $115.5$
• C. $1155$
• D. $1.155$

Answer 1

The correct option is C $1155$

Half life, $t_{1/2}=\frac{0.693}{K}=\frac{0.693}{6\times {10}^{-4}}=\frac{693\times {10}^{-3}}{6\times {10}^{-4}}=1155sec$