How many molecules are present in a #20*g# mass of #"carbon dioxide"#?

1 Answer
Sep 27, 2016

Approx. #3.0xx10^23" carbon dioxide molecules"#

Explanation:

#"Avogadro's number"# #=# #6.022xx10^23*mol^-1#.

Now, in #44*g# of gas there are #"Avogadro's number"# of molecules by definition.

And thus #6.022xx10^23*mol^-1# #xx# #(20*g)/(44.0*g*mol^-1)# #~=# #3.0xx10^23" carbon dioxide molecules"#. You can make a better estimate.