Question

In a liquid phase second reaction '90%' of the reactant converts to products in 3 minutes. Calculate the time required to convert 'A rarr R,70%' of the reactant.

Answer 1

Answer:

Correct option is

D

347 s

For first order reaction,

A⟶B

Rate =k×[A]

Given, rate =2.0×10

−5

molL

−1

s

−1

[A] = Conc. of A = 0.01 M

So, 2.0×10

−5

=k×0.01

k=

0.01

2.0×10

−5

s

−1

=2.0×10

−3

s

−1

For first order reaction,

t

1/2

=

k

0.693

=

2.0×10

−3

0.693

=346.5=347s