Half life of a radioactive material is 5 years, then the percentage of it remained after 25 years will be

Step-by-step solution

Here, t=25 years, T_ 1 / 2 =5 years Number of half lives, n= t T_ 1 / 2 = 25 5 =5 Percentage of radio active material remained after aligned 25 years is & = ( 1 2 )^n 100 & = ( 1 2 )^5 100=3.125 % aligned