Answer:
molar mass of the phosphorus chloride = 138.06 g/mol
Explanation:
mass of phosphorus will be the same as mass of CO2, since it is stated that they are of equal amount.
mass = 3.51 g
lets assume that it took the CO2 1 sec to effuse, then the time taken by the phosphorus chloride will be 1.77 sec
From this we can say that
rate of effusion of CO2 = 3.51/1 = 3.51 g/s
rate of effusion of the phosphorus chloride = 3.51/1.77 = 1.98 g/s
From graham's equation of effusion,
[tex]\frac{Rc}{Rp}[/tex] = [tex]\sqrt{\frac{Mp\\}{Mc} }[/tex]
Rc = rate of effusion of CO2 = 3.51 g/s
Rp = rate of effusion of phosphorus chloride = 1.98 g/s
Mc = molar mass of CO2 = 44.01 g/mol
Mp = molar mass of the phosphorus chloride = ?
Imputing values into the equation, we have
[tex]\frac{3.51}{1.98}[/tex] = [tex]\sqrt{\frac{Mp\\}{44.01} }[/tex]
1.77 = [tex]\frac{\sqrt{Mp} }{6.64}[/tex]
11.75 = [tex]\sqrt{Mp}[/tex]
Mp = [tex]11.75^{2}[/tex]
Mp = molar mass of the phosphorus chloride = 138.06 g/mol