## Chemistry: A Molecular Approach (3rd Edition)

$7.06\times10^{23}\ molecules$
Convert grams into moles using the molar mass then multiply by avagadro's number to get the number of molecules. $389g\ CBr_{4}\times\frac{1mol\ CBr_{4}}{331.63g\ CBr_{4}}\times\frac{6.022\times10^{23}\ molecules}{1\ mol}= 7.06\times10^{23}\ molecules$