What is the mass in grams of #2.10 * 10^21# atoms of copper, #Cu#?

1 Answer
Apr 2, 2016

There are #N_A# individual copper atoms in a moles of copper metal, and this has a mass of #63.55# #g#.

Explanation:

So we know that #"Avogadro's number"(N_A)# of individual copper atoms have a mass of #63.55# #g#.

Thus #(2.10xx10^21"copper atoms"xx63.55*g*mol^-1)/(6.022140857(74)×10^23 "copper atoms " mol^-1)# #=# #??g#