Question

Two radioactive nuclei P and Q, in a given sample decay into a stable nucleus R. At time t = 0, number of P species are 4 N₀ and that of Q are N₀. Half-life of P (for conversion to R) is 1 minute where as that of Q is 2 minutes. Initially there are no nuclei of R present in the sample. When number of nuclei of P and Q are equal, the number of nuclei of R present in the sample would be(a) 3N₀(b) 9N₀/2(c) 5N₀/2(d) 2N₀

Answer 1

HEY MATE HERE'S YOUR ANSWER ;

When number of nuclei of P and Q are equal, the number of nuclei of R present in the sample would be

5N₀/2

Answer 2

Answer:

9No/2

Explanation:

No. of P species at time t=0 is 4No

Half life of P is 1 min

After 1st half life the number of P species = 2No

Then, After 2nd half life the number of P species = No

Then, After 3rd half life the number of P species = No/2

Then, After 4th half life the number of P species = No/4

Total time = 4 minutes.

Hence, R = 4No– No/4

No. of Q species at time t=0 is No

Half life of Q is 2 min

After 1st half life the number of Q species = No/2

Then, After 2nd half life the number of Q species = No/4

Total time = 4 minutes

Hence, R = No – No/4

Total R = [4No – No/4] + No – No/4 = 15No/4 +3/4 No = 9No/2