For the first order reaction ${t_{{\rm{av}}}}$ (average life), ${t_{\frac{1}{2}}}\,\,\,\,{\rm{and}}\,\,\,\,{t_{\frac{3}{4}}}$ in the increasing order are

${t_{\frac{1}{2}}}\, < \,{t_{{\rm{av}}}} < \,\,{t_{\frac{3}{4}}}$

${t_{\frac{1}{2}}}\, < \,\,{t_{\frac{3}{4}}} < \,{t_{{\rm{av}}}}$

$\,{t_{{\rm{av}}}} < {t_{\frac{1}{2}}}\, < {t_{\frac{3}{4}}}$

$\,{t_{{\rm{av}}}} = {t_{\frac{1}{2}}}\, < {t_{\frac{3}{4}}}$

NEET UG CHEMISTRY MCQ: CHEMICAL KINETICS

1 Hard

1 of 1

Understanding +4 | -1

For the first order reaction

{t_{\mathrm{av}}}

(average life),

{t_{\frac{1}{2}}}\,\,\,\,\mathrm{and}\,\,\,\,{t_{\frac{3}{4}}}

in the increasing order are

View answer and explanation

Correct option: A

{t_{\frac{1}{2}}}\, < \,{t_{\mathrm{av}}} < \,\,{t_{\frac{3}{4}}}

Option A (

{t_{\frac{1}{2}}}\, < \,{t_{\mathrm{av}}} < \,\,{t_{\frac{3}{4}}}

) is correct because for a first-order reaction, the half-life is less than the average life, which is less than the time for 75% completion.