Question

Neon has three stable nautrally occurring isotopes. The isotopic mass and percent abundance of these isotopes are given inthe table.Isotope20 Ne21 Ne22 NeIsotopic mass (u)19.9920.9921.99Abundance (%)90.480.2279.25Calculate the average atomic mass of neon.

Answer 1

To calculate the average mass of Ne (neon), we have to use this formula:

`\text{Average atomic mass = }\frac{\sum ^{}_{}(\text{mass of isotopes)x(abundance \%)}}{100}`
`\begin{gathered} \text{Average atomic mass = }\frac{(19.99ux90.48+20.99ux0.27\text{ +}21.99ux9.25)}{100} \\ \text{Average atomic mass = }20.18\text{ u} \end{gathered}`

The average atomic mass of Ne = 20.18 u