# The atomic weight of a newly discovered element is 10.600 amu. It has two naturally occurring isotopes. One has a mass of 10.000 amu and a natural abundance of 70.000%. What is the isotopic mass of the other isotope?

##### 1 Answer

Nov 7, 2015

The atomic mass is the weighted average of the individual isotopes. You have 1 equation, and 1 unknown.

#### Explanation:

So,

So solve for *A priori* would you expect