What is the molar mass of a gas with a density of 3.50 g/L at a
temperature of 345 K and a pressure of 0.950 atm? (Write your
answer whole number e. g. 345)
g/mol

104 g/mol

Explanation:

Use the ideal gas equation:

     

Where:

p is pressure: 0.950atmV is volume: unknownn is number of moles: unknownR is the universal constat of gases: 0.08206 atm.liter/ (K.mol)T is the absolute temperature: 345K

Use the molar mass of the gas to include the density in the formula:

molar mass = mass in grams / number of moles⇒ mass in grams = number of moles × molar mass density = mass in grams / volume⇒ density = number of moles × molar mass / volumedensity = (n/V) × molar mass⇒ n/V = density / molar mass

Clear n/V from the gas ideal equation and subsittute with density/molar mass:

n/V = p/(RT)density / molar mass = n/Vdensity/molar mass = p/(RT)molar mass = density × RT / p

Now you can subsitute the data:

molar mass = (3.50g/liter) × 0.08206 atm.liter/(K.mol) × 345K / 0.950 atm

molar mass = 104.3 g/molRound to the nearest whole number: 104g/mol ← answer