How many copper atoms in a #63.55*g# mass of copper metal?

1 Answer
Feb 13, 2017

Answer:

By definition, there are #N_A, "Avogadro's number"# of copper atoms in a #63.55*g# mass of copper wire.

Explanation:

And #N_A, "Avogadro's number"# #=# #6.022xx10^23# individual copper atoms.

I look on the Periodic Table, and at #Z=29#, i.e. copper, the quoted atomic mass is #63.55*g#. The quoted mass is the mass of #"Avogadro's number"# of copper atoms. And thus, given a reaction with, say, oxygen or sulfur, I can calculate an equivalent, STOICHIOMETRIC mass of sulfur or oxygen.

My advice is to look at the Periodic Table, and get to know it; you will soon learn the atomic masses of the common reagents.