# What is the average atomic mass for neon?

## Neon-20 has a mass of 19.9924 amu Neon-21 has a mass of 20.9940 amu Neon-22 has a mass of 21.9914 amu The relative abundance of 20Ne is 90.92% and 21 Ne is .257% and 22 Ne is 8.82%.

This is simply the weighted average of the individual isotopes, which gives $20.1797 \cdot \text{amu}$
$N {e}_{\text{Average atomic mass}}$ $=$ (19.9924xx90.92%+20.9940xx0.257%+21.9914xx8.82%)*"amu" $=$ ??"amu"