Question

The half life of radioactive substance is $6$ years. The time taken by $12$ $gms$ of this substance to decay completely will be

• A. $\infty$
• B. $48$ years
• C. $18$ years
• D. $72$ years

Answer 1

The correct option is A $\infty$

Time required to decay completely is $Halflife\times {\log }_2\left(12/0\right)=6years\times \infty =\infty$