A sample of 245Am has a t1/2 of 7.37 × 10^3 y and an activity value, A, of?

Question

A sample of 245Am has a t1/2 of 7.37 × 10^3 y and an activity value, A, of 1.00 Bq. How many nuclei are there initially and after 1,000 years.

a. Ni = 3.35 × 1011 nuclei;
N1000 = 2.32 × 1011 nuclei.

b Ni = 3.35 × 1011 nuclei;
N1000 = 3.05 × 1011 nuclei.

c Ni = 2.32 × 1011 nuclei;
N1000 = 3.32 × 1011 nuclei.

d Ni = 1.06 × 104 nuclei;
N1000 = 9.7 × 103 nuclei.

Answer 1

dNi = 1.06 × 104 nuclei;
N1000 = 9.7 × 103 nuclei.