Question

What mass of sulfur must burn to produce 3.42 L of So2 at STP

Answer 1

Number of moles SO2 :

1 mol SO2 -------- 22.4 L ( at STP )
? mol SO2 --------- 3.42 L

1 x 3.42 / 22.4 => 0.152 moles of  SO2

Therefore:

Molar mass SO2 => 64.066 g/mol

1 mole SO2 ---------- 64.066 g
0.152 moles SO2 ---- ( Mass of SO2)

Mass of SO2 = 0.152 x 64.066 / 1

Mass of SO2 = 9.738 g