Calculate the molar mass of a gaseous substance if 0.125 g of the gas occupies 93.3 mL at STP.
A) 30.0 g/mol
B) 30.2 g/mol
C) 30.4g/mol
D) 30.6 g/mol
E) None of the above

Question

Quizplus · Accepted Answer

The molar mass of a gas can be calculated using the ideal gas law:PV = nRTwhere P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.At STP, the pressure is 1 atm and the temperature is 273.15 K. Substituting these values into the ideal gas law, we get:1 atm * 93.3 mL = n * 0.0821 Latm/(molK) * 273.15 KSolving for n, we get:n = 0.00401 molThe molar mass of the gas is then:molar mass = mass / moles= 0.125 g / 0.00401 mol= 30.0 g/molTherefore, the correct answer is A.

Calculate the Molar Mass of a Gaseous Substance If 0