Science Buddies: "Ask an Expert"

How do you calculate the average atomic mass for neon if its abundance in nature is 90.5% neon-20, 0.3% neon-21, and 9.2% neon-22?

Hi,
Is this related to a science experiment please? If so, please give us a little more details about the experiment.
Thanks!
Willey

Hi alexdudek,

A much simpler, perhaps silly, example can sometimes reveal an approach:

"element X is 50% X-20 and 50% X-30"

or

"half of X is 20, the other half is 30"

Remember that 50% is the fraction 50/100 ("fifty per cent") or 0.50

0.50 * 20 + 0.50 * 30 = average atomic mass of X = 25

Apply this in more complex situations like the problem you stated above.

-John