Question

) An unknown gas was added to the same vessel at 0.0 ⁰C (initially under vacuum) until a final pressure of 113 kPa was reached. The mass of the vessel increased by 142.2g. What is the molar mass of the unknown gas (g/mol)? Suggest a possible identity for the gas. (Hint, it’s formula is AF2, what is A? Use your periodic table)

Molar mass of gas:
Identity of gas:

Answer 1

You start by using the ideal gas equation to calculate the molar mass: PV=nRT

2- change this to solve for M (g/mol) M = mRT/PV

3- plug in the numbers (always make sure they are in the same unit so that they may cancel)

P= 113 kPa= 1.115 atm

T= 273.15 (Kelvin temperature)

R= .0821 L x atm/K x mol (gas constant)

But you didn't provide the volume V of a vessel to suggest identity.