Question

The isomerization of methylisonitrile to acetonitrileCH3NC(g)→CH3CN(g)is first order in CH3NC . The rate constant for the reaction is 2.34×10−4 s−1 at 489 K .The half-life of the reaction when the initial {\rm [CH_3NC]} is 0.030 M is ________ {\rm s}.A. 1.43×105B. 3.37×10−4C. 4.28×103D. 2.14×103E. 2.96×103

Answer 1

Answer:

Option E, Half life = $2.96\times 10^3\ s$

Explanation:

For a first order reaction, rate constant and half-life is related as:

            $t_{1/2}=\frac{0.693}{k}$

Where,

$t_{1/2}$ = Half life

k = Rate constant

Rate constant given = $2.34\times 10^{-4}\ s^{-1}$

$t_{1/2}=\frac{0.693}{k}$

$=\frac{0.693}{2.34 \times 10^{-4}}=2.96\times 10^3\ s$

So, the correct option is option E.