Ch 201 Problem 2.32

2.32 Rubidium has two naturally occuring isotopes: rubidium-85 (atomic mass=84.9118 amu; abundance = 72.15%) and rubidium-87 (atomic mass=86.9092, abundance=27.85%). Calculate the average atomic mass of rubidium.

the average atomic mass is the sum of the fractional abundances of each isotope multiplied by the atomic mass of the isotope. To get from per cent abundance to fractional abundance, we divide the per cent abundance by 100:

mathcad doesn't deal in atomic mass units

DAC 7/11/14