Question

A nucleus ${}_{11}{}^{}\mathrm{N}{a}^{24}$ emits a $\mathrm{\beta }$-particle to change into magnesium $\left(\mathrm{Mg}\right)$.

1. Write the symbolic equation for the process.
2. What are numbers $24$ and $11$ called ?
3. What is the general name of ${}_{12}{}^{24}\mathrm{Mg}$ with respect to ${}_{11}{}^{24}\mathrm{N}a$

Answer 1

i. Nucleus ${}_{11}{}^{24}\mathrm{N}a$emits a $\mathrm{\beta }$-particle to changes into magnesium $\left(\mathrm{Mg}\right)$.

Emission of $\mathrm{\beta }$-particle $\left({}_{-1}{}^0\mathrm{\beta }\right)$ mass number remains same and atomic number increases by one unit.

The symbolic equation. ${}_{11}{}^{}\mathrm{Na}^{24}\to {}_{12}{}^{}\mathrm{M}^{24}+{}_{-1}{}^0\mathrm{\beta }$

ii. $24$ is the mass number of sodium $\left(\mathrm{Na}\right)$ and $11$ is the atomic number of sodium $\left(\mathrm{Na}\right)$ atom.

iii. ${}_{12}{}^{}\mathrm{Mg}^{24}$ and ${}_{11}{}^{}\mathrm{N}{a}^{24}$ having same mass number but different atomic number.

Atoms having same mass number but different atomic number is known as isobars.

Hence, ${}_{12}{}^{}\mathrm{Mg}^{24}$ and ${}_{11}{}^{}\mathrm{N}{a}^{24}$ are isobars.