Answer:
3.125g/mol
Explanation:
To find the molar mass of the gas, we need to initially find the number of moles (n) contained in the gas. To find the number of moles, we use the general gas law whose equation is:
PV=nRT
Where; P= Pressure
V= Volume occupied by gas
n= number of moles
R= general gas constant
(0.0821 L atm mol/K)
T= absolute temperature
According to the question; P= 2.0atm, V= 2.0L, n= ?, T= 298K
To find n, we make it the subject of the formula:
n= PV/RT
n= 2.0 × 2.0 / 0.0821 × 298
n= 4/ 24.4658
n= 0.16mol
If number of moles (n) of the gas is 0.16mol and it weighs 0.500g, its molar mass can be found using:
number of moles (n) = mass (g) / molar mass
Making MM subject of the formula;
molar mass = mass / number of moles
MM= 0.500/0.16
MM= 3.125
Hence, the molar mass of the gas is 3.125g/mol.
