How do you calculate molecular weight from vapor pressure?

Knowing the weight of the vapor and the volume, pressure, and temperature allows the calculation of the molecular weight using PV=nRT.

How is the molar mass of a substance calculated?

The molar mass is the mass of a given chemical element or chemical compound (g) divided by the amount of substance (mol). The molar mass of a compound can be calculated by adding the standard atomic masses (in g/mol) of the constituent atoms.

How do you calculate KF?

Divide the freezing point depression by the molal concentration so you have: Kf = delta Tf / cm. Insert the values for delta Tf and cm. For instance, if you have a solution with a molality of 0.455 which freezes at 3.17 degrees Celsius, then Kf would equal 3.17 divided by 0.455 or 6.96 degrees Celsius.

What is meant by Cryoscopic constant KF?

Cryoscopic constant : It is the depression of freezing point of the solvent produced on dissolving one mole of a substance in 1000 g of it. It is also called molal depression constant.

What is the formula of Vapour?

Water vapor

Water vapor (H2O)
Molecular formula	H2O
Molar mass	18.01528(33) g/mol
Melting point	0.00 °C (273.15 K)
Boiling point	99.98 °C (373.13 K)

How does molar mass affect vapor pressure?

The bigger the molecule is and the more electrons it has, the bigger the London forces are. Bigger molecules usually have larger molecular weights; hence the correlation of vapor pressure with molecular weight.

How do you find the molar mass of a vapor?

First the ideal gas law will be used to solve for the moles of unknown gas (n). Then the mass of the gas divided by the moles will give the molar mass. Step 2: Solve. Now divide g by mol to get the molar mass.