Question

Which reaction is an example of alpha decay?

Group of answer choices

a Radium-225 transforms into Actinium-225
b Bismuth-209 transforms into Thallium-205
c Nickel-59 transforms into Cobalt-59
d None of these are alpha decay.

Answer 1

In the reaction Bismuth-209 transforms into Thallium-205, it is an example of alpha decay.

Step-by-step explanation:

Alpha decay involves the release of helium ions from the nucleus of an atom. It is characterized by the emission of an alpha particle, which consists of two protons and two neutrons and has a charge of 2+.

In the reaction a) Radium-225 transforms into Actinium-225, there is no change in the atomic number, so it is not an example of alpha decay.

In the reaction b) Bismuth-209 transforms into Thallium-205, the atomic number decreases by 2 and the atomic weight decreases by 4, which is characteristic of alpha decay.

Therefore, option b) is an example of alpha decay.