Heavy water, D2O (molar mass 20.03) can be separated from ordinary water by the difference in the relative rates of diffusion of the molecules in the gas phase. Calculate the relative rate of diffusion of H2O to D2O. (Atomic weights: O

1.58

Explanation:

This problem can be solved by using a law that was proposes in the year 1848, the law is known as the Graham's law of effusion. The law shows the relationship between square root of the density of a particular gas and the rates of effusion. The Graham' s law can be represented mathematically by using the formula below;

(NOTE: the question asked us to Calculate the relative rate of diffusion of H2O to D2O).

==> Rate of H2O effusion/ rate of D2O effusion = √ ( M{D2O} / M{H2O} ).

Also, we should know that Graham's law shows the relationship between the square root of density and the rate of effusion it can also show the relationship between the square root of the molar mass and the rate of effusion.

So, by using the Graham's law formula we will have;

Rate of H2O effusion/ rate of D2O effusion = √ ( M{D2O} / M{H2O} ). Where the molar mass of H2O = 18 gmol^- and D2O molar mass = 20 grams per mole.

Rate of H2O effusion/ rate of D2O effusion = √ (20/ 18).

Rate of H2O effusion/ rate of D2O effusion = √ 2.5.

Rate of H2O effusion/ rate of D2O effusion = 1.58.

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according to kinetic-molecular theory, the following would not be considered an ideal gas:

a gas at very low volumes, when gas particles are very close together

a gas at very low temperatures, when gas particles have very little kinetic energy a gas

a gas with highly polar molecules that have very strong intermolecular forces

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vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.