Question

First order reaction is 50% complete in 1.26 × 10¹⁴s. How much time could it take for 100% completion?

Options

• 1.26 × 10¹⁵s

• 2.52 × 10¹⁴s

• 2.52 × 10²⁸s

• Infinite

Answer 1

Infinite

Explanation:

The half-life period of a reaction is the time required for half of the reaction to complete, i.e., the time required for the concentration of a reactant to be reduced to half of its original value.

However, it is impossible to perform 100% of the reaction in which the entire substance reacts because, in every half-life, 50% of the substance reacts. As a result, the time required to complete a reaction completely is infinite.