Question

The half-life of a radioactive element is $8$ hours. A given number of nuclei of that element is reduced to $1/4$ of that number after two hours.

• A. True
• B. False

Answer 1

The correct option is B False

This statement is false because half life period is defined as the time during which half the amount of a given sample of the radioactive substance disintegrates.

Since half life period of the element is $8$ hours, it is not possible for the element to reduce to $1/4$ after two hours. It would take $16$ hours ($2$ half lifes) for the element to reduce to $1/4$ of the initial number