U8Q1 - Colligative Properties

Molality

mol solute/kg solvent

1 g =

0.001 kg (divide by 1000)

Molecular van’t hoff

1

Ion pairing

dissolved ions temporarily attract and become one particle, this makes i value slightly less then expected bc all ions are not always completely dissassociated

What happens to boiling point when a solvent dissolves as a solvent to become a solution

Solute particles form hydration spheres and organize solvent particles. Takes more energy to break these solute-solvent attractions and allow solvent particles to break attractions and escape into the gas phase. Also since the vapor pressure is lowered it will take more energy (heat) to increase the vapor pressure to equal the atmospheric pressure.

What happens to freezing point when a solvent dissolves as a solvent to become a solution

Solute particles interact with the solvent particles disrupting the interactions between the solvent particles. This makes it harder to form the attractions required to fix particles in space to become a solid. Lower temperature must be reached to achieve this crystal structure

What happens to vapor pressure when a solvent dissolves as a solvent to become a solution

Solute particles form hydration spheres and organize solvent particles. Takes more energy to break these solute-solvent attractions and allow solvent particles to break attractions and escape into the gas phase lowering the amount of particles that are able to escape into the gas phase.

What happens to osmotic pressure when a solvent dissolves as a solvent to become a solution

Osmotic pressure is due to nature’s favor of disorder (entropy). When there are two concentrations on two sides of a semipermeable membrane the water solvent will move to try and make the concentrations equal. This movement will continue until the osmotic pressure is equal to the atmospheric pressure on the other side. The higher the concentrations of particles the higher this osmotic pressure.