Question

How many alpha particles are emitted in the series of radioactive decay events from a U-238 nucleus to a Pb-206 nucleus?

Answer 1

Answer: 8 alpha particles

Explanation:-

Alpha decay : When a larger nuclei decays into smaller nuclei by releasing alpha particle. In this process, the mass number and atomic number is reduced by 4 and 2 units respectively.

General representation of alpha decay :

`_Z^A\textrm{X}\rightarrow _(Z-2)^(A-4)Y+_2^4\alpha`

`_(92)^(238)\textrm{U}\rightarrow _(82)^(26)\textrm{Pb}+_2^4\textrm{He}`

As the mass should remain same after the decay, we can use:

238=206+(4x)

Solving for x, we get:

x= 8.

Thus 8 alpha particles are emitted in the series of radioactive decay events from a U-238 nucleus to a Pb-206 nucleus.