Question

If there are 9.02x103 amu of copper in a sample, how many copper atoms are there in the sample?

Answer 1

Answer:

Average atomic mass = 63.62 amu

Explanation:

Average atomic mass is the weighted average of the individual isotopes.

And thus the weighted average =

(0.6917×63+0.3083×65)⋅amu = ?? amu.

Note that we have not accounted for the less massive copper isotopes that would decrease this mass to the accepted value of

63.55 amu.

Hope this helps! Good luck!