Question

The decomposition a → b + c of a molecule a obeys the rate-law expression rate = 0.080 min−1 [a]. if the initial concentration of a is 0.30 m, what is the concentration after 2.6 minutes? 1. 0.028 m 2. 0.24 m 3. 0.38 m 4. 0.13 m 5. 0.32 m 0

Answer 1

The correct option from given choices is 2, that is 0.24 m
We can find this by using the following formula;
ln A = ln Ao - kt
Ao = 0.30
k = 0.080 min⁻¹
t = 2..6 min
ln A = ln 0.30 - (0.080 min⁻¹) (2.6 min)

ln A = -1.412

A = 0.24 m