Question

In a reaction, 2A→ products, the concentration of A decreases from 0.50 M to 0.38 M in 10 min. What is the rate of reaction (in M s−1) during this interval?

1) 0.024
2) 1
3) 2×10−4
4) 0.2×10−4​

Answer 1

The reaction taking place is:

2A ---------> Products.

Given, The concentration of A decreases from 0.5 M to 0.38 M in 600 s.

Change in concentration = 0.5 - 0.38 => 0.12 M

Rate of reaction(in Ms-1) = 0.12/600 =>1/5000

=> 1/5 x 10^-3

=> 0.2 x 10^-3

=>2 x 10^(-3-1)

=> 2 x 10^-4 M s-1

So, (3) is the correct answer.