Final answer:
The average mass of copper (Cu) is 63.55 g/mol, taking into account the different masses and abundances of its isotopes.
Step-by-step explanation:
The relative atomic mass of an element is the average mass of all the naturally occurring isotopes of that element. The average mass of copper (Cu) is 63.55 g/mol, taking into account the different masses and abundances of its isotopes.
In the case of copper (Cu), it has two stable isotopes: 63Cu with an abundance of 69.09% and a mass of 62.929595 g/mol, and 65Cu with an abundance of 30.91% and a mass of 64.927786 g/mol.
To calculate the average mass of copper, we use the masses of the isotopes and their abundances. We multiply the mass of each isotope by its abundance and then add them together. For copper, the average mass would be:
(62.929595)(0.6909) + (64.927786)(0.3091) = 63.55 g/mol