Question

Copper(Cu) is made up of 69.1% 63Cu and 30.9% 65Cu.

The atomic mass of 63Cu is 62.9296 amu. The atomic mass of 65Cu is 64.9278 amu.

What is the average atomic mass of copper?

Responses

64.000 amu
64.000 lowercase a m u

63.547 amu
63.547 lowercase a m u

63.929 amu
63.929 lowercase a m u

64.310 amu

Answer 1

63.547 amu

Calculation: (0.691)(62.9296) + (0.309)(64.9278) = 43.4843536 + 20.0626902 = 63.5470438 ≈ 63.547 amu.