Answer
a: SF2 (l) +2F2 (g) ---> SF6 (g)
b: 8.59 x 10^19 molecules
c: 4.26 L F2
Work Step by Step
1 Sulfur Difluoride + 2 Fluorine gas ---> 1 gaseous Sulfur Hexafluoride
5.00mg SF2 x (1g SF2 / 10^3 mg SF2) x (1 mol SF2 / 70.1g SF2) x (2mol F2 / 1mol SF2) x (6.02 x 10^23 molecules F2 / 1 mol F2) = 8.59 x 10^19 molecules
6.66g SF2 x (1 mol SF2 / 70.1g SF2) x (2mol F2 / 1mol SF2) x (22.4 L F2 / 1 mol F2) = 4.26 L F2
