Q.No.198: - How much of a 1g sample of pure radioactive mater would be left after four half-lives?

Q.No.198: - How much of a 1g sample of pure radioactive mater would be left after four half-lives?

Ans: - Amount of sample of pure radioactive matter         =      1g

           After 1^st half life 1T_1/2                                                 =   1/2g=0.5g

           After 1^st half life 2T_1/2                                                 =   0.25g

           After 1^st half life 3T_1/2                                                 =    0.125g

           After 1^st half life 4T_1/2                                                 =    0.0625g