Answer:
The molar mass of the unknown gas is 40.06 g/mol
Explanation:
Graham's law of effusion states that the rate of effusion of a gaseous substance is inversely proportional to the square root of its molar mass.
[tex]\frac{R_{b} }{R_{a} } = \sqrt{\frac{M_{a} }{M_{b} } }[/tex] [tex]= \frac{t_{a} }{t_{b} }[/tex] where R = rate of effusion, M = molar mass and t= time of effusion
⇒ [tex]\sqrt{\frac{2 g/mol}{x g/mol} } = \frac{162secs}{725secs}[/tex]
x g/mol = [tex]\frac{2}{0.223448^{2} }[/tex]
= 40.06 g/mol
