Chapter 2.2: Physical Properties of Solutions

Solubility

defined as the maximum amount of a solute that will dissolve in a given quantity of solvent at a specific temperature

Directly Proportional

What’s the relationship between the solubility of solid and temperature?

Fractional crystallization

separation of a mixture of substances into pure components on the basis of their differing solubilities.

Steep solubility curve

What does the compound needs to have to be in Fractional Crystallization

Warmer water holds less dissolved oxygen, making it harder for aquatic organisms to survive.

Why does thermal pollution affect aquatic life?

No, external pressure has little effect on their solubility.

Does pressure affect the solubility of solids and liquids?

Henry’s Law

The solubility of a gas in a liquid is directly proportional to the pressure of the gas over the solution.

Directly Proportional

Relationship between solubility of a gas and pressure

The pressure is released, and dissolved CO₂ escapes, causing effervescence.

What happens when a bottle of soda is opened?

Osmosis

The movement of solvent molecules through a semipermeable membrane from a dilute solution to a more concentrated one.

osmotic pressure

The pressure required to stop osmosis

It remains the same size because there is no net movement of water.

What happens to a red blood cell in an isotonic solution?

It swells and may burst because water moves into the cell.

What happens to a red blood cell in a hypotonic solution?

It shrinks (crenates) because water moves out of the cell.

What happens to a red blood cell in a hypertonic solution?

The loss of water from leaves, which creates osmotic pressure to pull water upward through the plant.

What is transpiration in plants?

Colloid

A dispersion of particles of one substance throughout a dispersing medium of another substance.

They are larger than solute molecules but smaller than suspension particles.

How do colloidal particles compare in size to solute molecules?

Tyndall effect

The scattering of light by colloidal particles, making the beam of light visible.

Solute molecules in a true solution are too small to scatter light.

Why don’t true solutions exhibit the Tyndall effect?

Hydrophilic colloids

Water-loving colloids that easily disperse in water (e.g., proteins, starch).

Hydrophobic colloids

Water-fearing colloids that do not easily disperse in water (e.g., oil in water).

Soap molecules surround grease, forming micelles, where the nonpolar tails dissolve in grease and the polar heads interact with water.

How does soap help remove grease?

1 x 10^3 pm to 1 x 10^6 pm.

Range of colloidal particles

Hypertonic

The more concentrated solution with unequal osmotic pressure

Hypotonic

The more dilute solution with unequal osmotic pressure

Semipermeable membrane

which allows the passage of solvent molecules but blocks the passage of solute molecules

c=kP

Solution of Henry’s Law

MRT

osmotic pressure solution