the number of grams of H2 in 1920 mL of H2 gas

Question

Use the molar volume to calculate each of the following at STP:

Answer 1

At STP, 1 mole of an ideal gas = 22.4 liters.

1920 ml of H₂ x 1 L/1000 ml x 1 mole/22.4 liters x 2 .00 g H₂/mole H₂ = 0.171 g H₂ (to 3 significant figures)

Looking at the above calculation in steps, we have:

1920 ml of H₂ x 1 L/1000 ml = 1.920 liters of H₂

1.920 liters H₂ x 1 mol/22.4 liters = 0.0857 moles of H₂

0.0857 moles H₂ x 2.00 g H₂/mole H₂ = 0.171 g H2