Question

The following procedure is a simple though somewhat crude

wayto measure the molar mass of a gas. A liquid of mass 0.0184 g
isintroduced into a syringe by injection through a rubber tip using
ahypodermic needle. The syringe is then transferred to a
temperaturebath heated to 45 degrees C and the liquid vaporizes.
The finalvolume of the vapor (measured by the outward movement of
theplunger) is 5.58 mL and the atmospheric pressure is 760 mmHg.
Giventhat the compound's empirical formula is CH2,determine the
molar mass of thecompound.

Answer 1

86.1 g

Step-by-step explanation:

To calculate the molar mass of the compound, use theformula

PV = nRT

Where P = 1atm

V = 0.00558L

R= 0.0821L.atm/mol.K

T = (273+ 45)K = 318 K

n = moles = mass(g) / molar mass(g/mol)

Hence, we have

n = PV/RT

= (1*0.00558)/(0.0821/318)

n = 0.0002137

hence molar mass of the compound = mass/ n

where mass = 0.0184 g

Hence, molar mass = 0.0184/0.0002137 = 86.1 g