Question

N2O5(g) → NO3(g) + NO2(g)

Answer 1

Answer:

It will take 77.8 seconds for 95% of sample to react

Explanation:

As the given reaction obeys 1st order therefore-

                        $[N_{2}O_{5}]=[N_{2}O_{5}]_{0}\times (\frac{1}{2})^{\frac{t}{t_{\frac{1}{2}}}}$

Where $[N_{2}O_{5}]$ is the concentration of $N_{2}O_{5}$ after "t" time, $[N_{2}O_{5}]_{0}$ is the initial concentration of $N_{2}O_{5}$ and $t_{\frac{1}{2}}$ is half life

Here, $\frac{[N_{2}O_{5}]}{[N_{2}O_{5}]_{0}}=\frac{100-95}{100}=0.05$ and $t_{\frac{1}{2}}=18.0 seconds$

So, $0.05=(\frac{1}{2})^{\frac{t}{18.0seconds}}$

or, $t=77.8 seconds$

So, it will take 77.8 seconds for 95% of sample to react