What is the mass in grams of #4.6*10^21# molecules of carbon tetrabromide?

1 Answer
Apr 15, 2016

#(4.6xx10^21" molecules")/(6.022xx10^23" molecules mol"^-1)xx331.61*g*mol^-1# #=# #??# #g#

Explanation:

#6.022xx10^23# molecules, i.e. a mole, of #CBr_4#, have a mass of #331.61*g#.

So the mass of your given number of molecules is:

#(4.6xx10^21*"molecules")/(6.022xx10^23*"molecules"*"mol"^-1)xx331.61*g*mol^-1=?*g#.