Question

In the following reaction, rate constant is
1.2 x 10-2 Ms-¹A---> B. What is concentration
of B after 10 min., if we start with 10 M of A.
(1) 2.8 M
(2) 7.2 M
(3) 8.2 M
(4) 2.7 M​

Answer 1

Answer:

The correct option is (2).

Explanation:

Integrated rate law for first order kinetics is given as:

$k=\frac{1}{t}([A_o]-[A])$

k = rate constant of the reaction

$[A_o]$ = Concentration of reactant initially.

$[A]$ = Concentration of reactant at time t.

Concentration of a after ten minutes t  = 10 min = 600 sec

$[A_o]=10 M$

$1.2\times 10^{-2} \times Ms^{-1}=\frac{1}{600 s}(10 M - [A])$

[A] = 2.8 M

After a duration of ten minutes the concentration of A left is 2.8 M.This means that (10M-2.8 M) of A has converted into B.

So, the concentration of B = (10M-2.8 M ) = 7.2 M.

Answer 2

Answer:

option 1

Explanation: