If you are given #2.13 x10^24# atoms Au, how do you determine the moles in the sample and the mass of the sample?

1 Answer
Dec 4, 2016

Answer:

Divide the given number by #"Avogadro's number"#, and then mulitply this number, the number of #"moles of gold"# by the #"molar mass"# of gold.

Explanation:

#"Moles of gold atom"# #=# #(2.13xx10^24" gold atoms")/(6.022xx10^23" gold atoms"*mol^-1)#

#~=# #3.5*mol#

And then we multiply this number by the molar mass of gold:

#3.5*molxx197.0*g*mol^-1# #~=# #700*g#

Today's price of gold is #$38-00" USD "g^-1#.

How much is your mass worth?