What is the relationship between molecular weight and intermolecular forces?
When the weight of individual gas molecules becomes significant, London dispersion forces, or instantaneous dipole forces, tend to increase, because as molecular weight increases, the number of electrons within each gas molecule tends to increase as well.
What is the relationship between intermolecular forces and vapor pressure?
A liquid’s vapor pressure is directly related to the intermolecular forces present between its molecules. The stronger these forces, the lower the rate of evaporation and the lower the vapor pressure.
How does molecular mass affect intermolecular forces?
The strength of London forces depends on the molar mass of the molecule (higher MM → more electrons → more polarizable → stronger London forces) and, to a lesser extent, on surface area (greater surface area→ stronger London forces). The greater the polarity, the stronger the dipole-dipole forces.
What is the relation between Vapour density and molecular mass?
vapour density = mass of n molecules of gas / mass of n molecules of hydrogen. (and thus: molar mass = ~2 × vapour density) For example, vapour density of mixture of NO2 and N2O4 is 38.3 . Vapour density is a unit less quantity.
What happens when a molecular weight increases?
A High molecular weight increases the chemical resistance – to a point. It takes more damage to the main chains of the molecules before it will affect the strength of the material. A High molecular weight increases the viscosity of the material – makes it harder to process the material using conventional methods.
How does molecular structure affect vapor pressure?
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 is the relationship between molecular and pressure?
As the number of molecules increases, the number of collisions and thus the pressure increase. Similarly, the gas pressure is higher if the average velocity of molecules is higher.
What intermolecular forces increase molecular mass?
Dispersion forces tend to increase with increasing molar mass.
What is the relationship between diffusion and molecular weight?
Graham’s law states that the rate of diffusion or of effusion of a gas is inversely proportional to the square root of its molecular weight.
How does molecular size and mass affect the diffusion?
Mass of the molecules diffusing: Heavier molecules move more slowly; therefore, they diffuse more slowly. The reverse is true for lighter molecules. Temperature: Higher temperatures increase the energy and therefore the movement of the molecules, increasing the rate of diffusion.
What is the relationship between molecular weight and diffusion quizlet?
the lower the molecular weight, the faster the rate of diffusion. the higher the molecular weight, the slower the rate of diffusion.
