Ahypothetical element has an atomic weight of 48.68 amu. it consists of three isotopes having masses of 47.00 amu, 48.00 amu, and 49.00 amu. the lightest-weight isotope has a natural abundance of 10.0%. what is the percent abundance of the heaviest isotope?

78 %

Explanation:

The atomic mass is the weighted average of the atomic masses of each isotope.

In a weighted average, we multiply each value by a number representing its relative importance.

In this problem, the percent abundance represents the relative importance of each isotope.

Data:

X-47: mass = 47.00 u; abundance = 10.0 % = 0.100  

X-48: mass = 48.00 u  

X-49: mass = 49.00 u

Calculations:

                 Let x = abundance of X-49

Then 0.900 - x = abundance of X-48

The heaviest isotope has an abundance of 78 %.

points

explanation: