What happens to intermolecular forces when vapor pressure increases?
As the intermolecular attraction increases, • The vapor pressure ( the pressure of the vapor that is in equilibrium with its liquid) decreases • The boiling point ( the temperature at which the vapor pressure becomes equal to the pressure exerted on the surface of the liquid) increases • Surface tension ( the …
Do strong intermolecular forces have high heat of vaporization?
The stronger the intermolecular forces, the higher the heat of vaporization. The stronger the intermolecular forces, the lower the vapor pressure. Boiling Point. Temperature at which the vapor pressure of a liquid is equal to the external pressure.
When intermolecular forces are weak volatility is?
Volatility-The more volatile, the weaker the intermolecular forces. Vapor pressure-The higher the vapor pressure, the weaker the intermolecular forces. The melting point/boiling point is higher in substances that have stronger intermolecular forces. Other physical properties include viscosity.
Why the heat of vaporization is higher in value as compared to the heat of fusion of different substances?
Notice that for all substances, the heat of vaporization is substantially higher than the heat of fusion. Much more energy is required to change the state from a liquid to a gas than from a solid to a liquid. This is because of the large separation of the particles in the gas state.
Why does heat of vaporization decreases with increasing pressure?
As the density of liquid decreases, the intermolecular attractive forces decrease with distance, and thus the heat of evaporation decreases. 2) The vapour is compressed under increasing vapour pressure.
Which has lowest vapor pressure?
The substance with the highest boiling point will have the lowest vapor pressure. Vapor pressure is a liquid property related to evaporation. In the liquid (or any substance) the molecules have a distribution of kinetic energies related to the temperature of the system.
Do larger molecules have higher 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.
Does low vapor pressure mean strong intermolecular forces?
Strong intermolecular forces produce a lower rate of evaporation and a lower vapor pressure. Weak intermolecular forces produce a higher rate of evaporation and a higher vapor pressure. As the temperature increases, the vapor pressure increases.
What are weak intermolecular forces?
Van der Waals Dispersion Forces (“London forces”) The weakest intermolecular forces of all are called dispersion forces or London forces. These represent the attraction between instantaneous dipoles in a molecule.