Complete Question:
Which answer choice represents a balanced alpha emission nuclear equation? A. 52 26 Fe --> 52 25 Mn+ 0 ⁺1 e. B. 235 92 U --▻ 239 94 Pu + 4 2 He C. 189 83 Bi --▻ 185 81 Tl + 4 2 He D. 14 6 C --▻ 14 7 N + 0 -1 e
Answer:
The balanced alpha emission nuclear equation is
[tex]\begin{array}{c}{189} \\{83}\end{array} B i \rightarrow \begin{array}{c}{185} \\{81}\end{array} T l+\frac{4}{2} H e[/tex]
Explanation:
In radioactivity, there are three major kinds of emission. They are alpha, beta and gamma emission. In alpha emission, the helium nuclei will be released. So the parent nuclei will undergo a change in their atomic and mass number.
As the atomic number of alpha particle is 2 and the mass number is 4, then on release of alpha particle, the parent nuclei will undergo a decrease in the atomic number by 2 and mass number by 4. So,
[tex]\begin{array}{c}{189} \\{83}\end{array} B i \rightarrow \begin{array}{c}{185} \\{81}\end{array} T l+\frac{4}{2} H e[/tex]
The above is the balanced alpha emission nuclear equation. As the atomic and mass number of parent element is equal to the sum of atomic and mass number of the daughter nuclei formed.
