Question

Calculate the molar mass of a vapor that has a density of 7.125 g/L at 13 ∘C and 741 torr .

Answer 1

To calculate the molar mass, you can use the ideal gas law equation and rearrange it to solve for the molar mass. For this question, the molar mass of the vapor is approximately 159.3 g/mol.

Step-by-step explanation:

To calculate the molar mass, we need to use the ideal gas law equation:

density = molar mass / molar volume

Given the density, we can rearrange the equation to solve for the molar mass:

molar mass = density × molar volume

Substituting the given values:

molar mass = 7.125 g/L × 22.41 L

molar mass = 159.29775 g/mol

Therefore, the molar mass of the vapor is approximately 159.3 g/mol.

Answer 2

Molar Mass = 171.6 g/mol

Step-by-step explanation:

Here we can use the equation PV = nRT, where n could stand for m / M, considering M = Molar Mass. Now we can rearrange this equation to isolate M, as we have to determine the " molar mass " of this vapor,

PV = ( m / M )RT,

density = mass / volume = PM / RT -

M = dRT / P

First convert celcius to kelvins and torr to " standard atmosphere " before plugging in the known values,

13 C = 286 K,

741 torr = 0.975 atm -

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M = (7.125)(0.0821) (286) / 0.975

M = 171.6 g /mol