Question

Polonium-191 decays by emitting an alpha particle. The daughter product also decays by alpha decay. What is the product of the two decays?

a.Hg-183
b.Hg-189
c.Po-197
d.Pb-193

Answer 1

The correct option is a: Hg-183.

Step-by-step explanation:

The alpha decay is given by:

`^(A)_(Z)X \rightarrow ^(A-4)_(Z-2)Y + ^(4)_(2)He`

Hence, if Polonium-191 decays by emitting an alpha particle we have:

`^(191)_(84)Po \rightarrow ^(187)_(82)Pb + ^(4)_(2)He`

Now, if Pb-187 also decays by emitting an alpha particle we have:

`^(187)_(82)Pb \rightarrow ^(183)_(80)Hg + ^(4)_(2)He`

Therefore, the correct option is a: Hg-183.

I hope it helps you!