A 2.2 L volume of ideal neon gas (monatomic) is at a pressure of 3 atmospheres and a temperature of 290K. The atomic mass of neon is 20.2 g/mol. The mass of the neon gas in SI units is?

Answer 1

For this I would just use the ideal gas law of PV=nRT, you can find the number of moles of gas. Then from there you can convert to mass using the molar mass given in the question.

(3atm)(2.2L) = n(0.08205 L atm mol^-1 K^-1)(290K)

n = 0.2774 mol of Neon

From there you know each mol of neon has a mass of 20.2grams, so you can say mass = n*molar mass

mass of neon = (0.2774)(20.2) = 5.603 grams of Neon in the tube