Question

Copper, a metal known since ancient times, exists in two stable isotopic forms, 6329Cu (69.09%) and 6529Cu (30.91%). Their atomic masses are 62.93 amu and 64.9278 amu respectively. Calculate the average atomic mass of copper.

Answer 1

Wt. Avg. Atomic Weight => 63.35457 amu

Step-by-step explanation:

Given Isotopic %Abundance fractional Wt Avg

At. Mass (amu) abundance contribution

Cu-63 62.93 69.09 0.6909 43.4783

Cu-65 64.9278 20.0668 0.200668 20.0668

Wt Average of all isotopes = ∑Wt Avg Contributions

= 43.4783 amu + 20.0668 amu = 63.35457 amu