Question

What is the activity of a sample of 146C that contains 1.2×1020 nuclei?

Answer 1

Given that a sample of ¹⁴C₆ that contains 1.2×10²⁰ nuclei.

                                    N = 1.2×10²⁰ nuclei

     For  ¹⁴C₆ , half life   t _1/2 = 5730 yrs = 5730 x 365 x 24 x 60 x 60 sec

We know that

         activity = λN

                      = (0.693/ t _1/2) N

                     = (0.693/ 5730 x 365 x 24 x 60 x 60 sec) x 1.2×10²⁰

                    = 460207033.4 s^-1

Thefore,

   activity of ¹⁴C₆ = 460207033.4 s^-1