Question

The half-life of a radioactive isotope:

• A. increases with time
• B. decreases with time
• C. remains constant
• D. varies with pressure
  

Answer 1

The correct option is C remains constant

The half life of a radioactive isotope is always Constant.
Radioactive decay is first order reaction and its half life period is independent of the initial activity. It is given by the expression $t_{1/2}=\frac{0.693}{\lambda }$