Question

Uppose you have two 1-L flasks, one containing a gas with a molar mass of 30 g and the other a gas with a molar mass of 60 g. Both flasks are at the same temperature, both gas samples have a mass of 1.2 g, but the pressure in Flask X is 1.0 atm and in Flask Y is 0.5 atm. Which flask contains the gas molar mass 30 g?

flask X
flask Y
not enough information problem.

Answer 1

The answer to your question is: Flask X

Step-by-step explanation:

Data

Flask X Flask B

Molar mass 30 g 60 g

mass 1.2g 1.2 g

Pressure 1 atm 0.5 atm

Formula PV = nRT

In the formula, we can notice that the number of moles (n)

is directly proportional to the pressure.

Then, let's calculate the number of moles

flask X flask Y

30 g --------------- 1 mol 60 g -------------- 1 mol

1.2 g ---------------- x 1.2 g ------------- x

x = (1.2 x 1) / 30 x = (1.2 x 1) / 60

x = 0.04 mol x = 0.02 mol

From the results, we conclude that the flask with the gas of molar mass 30g is the flask with pressure of 1 atm, because the higher the number of moles, the higher the pressure.