Question
Half-life period of a first order reaction is $$1386s.$$ The specific rate constant of the reaction is
A.
$$5.0 \times {10^{ - 3}}{s^{ - 1}}$$
B.
$$0.5 \times {10^{ - 2}}{s^{ - 1}}$$
C.
$$0.5 \times {10^{ - 3}}{s^{ - 1}}$$
D.
$$5.0 \times {10^{ - 3}}{s^{ - 1}}$$
Answer :
$$0.5 \times {10^{ - 3}}{s^{ - 1}}$$
Solution :
$$\eqalign{
& {\text{Specific rate constant,}} \cr
& k = \frac{{0.693}}{{{t_{\frac{1}{2}}}}} \cr
& \,\,\,\,\, = \frac{{0.693}}{{1386}} \cr
& \,\,\,\,\, = 0.5 \times {10^{ - 3}}{s^{ - 1}} \cr} $$