Hydrogen sulfide reacts with sulfur dioxide to give H2O and S, H2S + SO2 = H2O + S(solid), unbalanced. If 3.0 L of H2S gas at 760 torr produced 4.8 g of sulfur, what is the the temperature in Celsius?

You must convert

#"grams of S" → "moles of S" → "moles of H"_2"S"#

and then use the Ideal Gas Law to find the temperature of the #"H"_2"S"#.

1. Write the balanced equation.

The balanced equation is

#"2H"_2"S" + "SO"_2 → "2H"_2"O" + "3S"#

2. Calculate the moles of #"H"_2"S"#.

#"moles of H"_2"S" = 4.8 color(red)(cancel(color(black)("g S"))) × (1color(red)(cancel(color(black)("mol S"))))/(32.06color(red)(cancel(color(black)("g S")))) × ("2 mol H"_2"S")/(3color(red)(cancel(color(black)("mol S")))) = "0.0998 mol H"_2"S"#

3. Use the Ideal Gas Law to calculate the temperature of the #"H"_2"S"#.

#color(blue)(bar(ul(|color(white)(a/a)PV = nRTcolor(white)(a/a)|)))" "#

#P = 760 color(red)(cancel(color(black)("Torr"))) × "1 atm"/(760color(red)(cancel(color(black)("Torr")))) =" 1.00 atm"#

#T = (PV)/(nR) = (1.00 color(red)(cancel(color(black)("atm"))) × 3.0color(red)(cancel(color(black)("L"))))/(0.0998color(red)(cancel(color(black)("mol"))) × "0.082 06"color(red)(cancel(color(black)("L·atm")))·"K"^"-1"color(red)(cancel(color(black)("mol"^"-1")))) = "366 K"#

#T = "(366 – 273.15) K" = "90 °C"#

Note: The answer can have only 1 significant figure, because the Kelvin temperature has only 2 significant digits. If you need more precision, you will have to recalculate.