HELP ME PLEASE!

1. Calculate the weight of 16.2L of pure SO2 gas at STP. (answer in grams)
a.16.2
b.31.8
c.39.5
d.46.3
e.64.1

2.A volume of 725mL of a gas is collected at 105Celsius and 745torr. The gas weighs 1.93 grams. What is the Gas?
a.Fe2
b.Ar
c.Kr
d.Xe
e.Rn

1 answer

1 mol of gas at STP occupies 22.4 L. 1 mol of SO2 is 32+16+16.

Use PV = nRT for the second one. Solve for n, then use n = grams/molar mass. Use the molar mass to identify the gas from the list.