Answer:
19.46 g/mol
Explanation:
First of all, we have to calculate the number of moles of the gas. We can do it by using the ideal gas equation, which states that:
[tex]pV=nRT[/tex]
where we have:
p = 1.00 atm is the pressure of the gas
V = 1.00 L is the volume of the gas
n is the number of moles
[tex]R=0.082 atm L/(mol K)[/tex] is the gas constant
[tex]T=25.0^{\circ} C+273=298 K[/tex] is the Kelvin temperature of the gas
Solving for n,
[tex]n=\frac{pV}{RT}=\frac{(1.0)(1.00)}{(0.082)(298)}=0.041 mol[/tex]
Now we can calculate the molar mass of the gas, which is given by:
[tex]M=\frac{m}{n}[/tex]
where
m = 0.798 g is the mass of the gas
n = 0.041 mol is the number of moles
Substituting,
[tex]M=\frac{0.798}{0.041}=19.46 g/mol[/tex]
