contains neon has an internal volume of 6.88 L. A pressure gauge attached to the cylinder reads 1870 psi (1 atm =14.7 psi) at 22.1 ∘C. What mass of neon is contained in the cylinder?

Answer 1

Use the ideal gas law, PV = nRT

V = volume = 6.88 L

P = pressure = 1870 psi x 1 atm / 14.7 psi = 127.2 atm

T = temperature in Kelvin = 22.1C + 273 = 295.1K

n = moles = ?

R = gas constant = 0.0821 Latm/Kmol

Solving for mols of neon, we have ...

n = PV/RT

n = (127.2)(6.88) / (0.0821)(295.1)

n = 36.1 mols

Mass of neon = 36.1 mols x 20.2 g / mol = 730. g (3 sig. figs.)