Answer to Question #282930 in Atomic and Nuclear Physics for BIGIRMANA Elie

Question

Show that the mass of radium (Mass number= 226, half-life = 1600 yrs) with an

activity of a curie (1Ci) is almost 1gm.

Answer 1

The relation for specific activity (activity per gram) and the molar mass is

$$a=\dfrac{N_A\ln 2}{T_{1/2}M}=3.1·10^{10}\text{ Bq},$$

which is equivalent to 1 Ci.