H₂ Gas Calculation

First Calculate the volume of your gas:

(4/3p(2.1cm)³) = 39 cm³

For the Ideal Gas Equation we need the volume to be in liters:

1cm³ = 1 mL = 0.001 L; so 39 cm³ = 39 mL = 0.039 L

Then we plug in all the values we have collected into the ideal gas equation and solve for n (the number of moles):

PV = nRT

(1.0 atm)(0.039L) = n(0.08206 L.atm/mol.K)(298K)

n = 1.6 x 10^-3 mol

We then convert this amount to grams using the molecular weight of Hydrogen gas: 2.02 g/mol

1.6 x 10^-3 mol x 2.02 g/mol = 3.2 x 10^-3 grams H₂