Question

For the reaction `A + 2B rarr` products (started with concentration taken in stoichiometric proportion), the experimentally determined rate law is :
`-(d[A])/(d t) = ksqrt([A])sqrt([B])`
The half life time of the reaction would be :
A. `(0.693)/(k)`
B. `(0.693)/(1//k)`
C. `(0.693)/(sqrt(2k))`
D. not defined

Answer 1

Correct Answer - C
`{:(A,+,,2B rarr,"products"),(a-x,,,2a - 2x,):}`
`- (d[A])/(d t) = ksqrt([A])sqrt([B])`
Reactant are in their stoichiometric proportional
`rArr -(d(a-x))/(d t) = k = sqrt((a-x)) sqrt(2(a-x))`
`(d x)/(d t) = sqrt(2)k (a-x)" "t_(1//2) = (0.693)/(sqrt(2)k)`