Question

A sample of a gas weighs 2.566g and has a volume of 1010.0 ml at 845.0 torr and 25.0°C. what is its molar mass?

Answer 1

from the ideal gas equartion

P V = n R T

n = 845 X 0.00132 atm x 1.01 L ) / ( 0.0821 atm L /K mol x 298K )

= 0.046 mol

n = mass /molar mass

molar mass = 2.566 g / 0.046 mol

= 55.73 g/mol