Question

6. The polonium isotope 210

84 Po is unstable and emits a 5.30 MeV alpha particle. The

atomic mass of 210

84 Po is 20998 and that of 4

2He is 4.0026u. Identify the daughter nuclide

and find its atomic mass in u.

Answer 1

$_{84}^{210}Po\to _2^4He+_{82}^{206}Pb,$

$E=(m_{Po}-m_{He}-m_{Pb})c^2,$

$m_{Pb}=m_{Po}-m_{He}-\frac E{c^2}=205.9745~u.$