Question

How many fluorine atoms are present in 5.85 g of c2f4?

Answer 1

The molar mass of C2F4 (tetrafluoroethylene) is equal to 100 g/mol. The number of moles of C2F4 in the given amount,
                               n = (5.85 g) / (100 g/mol) = 0.0585 mols C2F4
The number of molecules per mol is calculated through the equation,
                          (0.0585 mols) x (6.022 x 10^23)
Since there are 4 F atoms each molecule then, 
                           (0.0585 mols) x (6.022 x 10^23)(4)
                          = 1.41 x 10^23 atoms of F