31.4 Exercise 21

In the following four problems, identify the parent nuclide and write the complete decay equation in the $_{Z}^{A} X_{N}$ notation. Refer to the periodic table for values of $Z$.

$\alpha$ decay producing $^{\text{228}} \text{Ra}$. The parent nuclide is nearly 100% of the natural element and is found in gas lantern mantles and in metal alloys used in jets ($^{\text{228}} \text{Ra}$ is also radioactive).