# Solutions and Colloids

## Vocabulary

### alloy

mixture of two or more metallic elements

### colloid

mixture containing particles that do not settle

### dispersed phase

substance with particles that are spread out and suspended in a colloid, analogous to the solute

### dispersion medium

substance in which the particles are suspended in a colloid, analogous to the solvent

### fractional distillation

separation of two liquids by boiling in stages

### Henry's law

law that states that the amount of a gas that dissolves in a certain type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid at a specific temperature, represented by the equation $C=kP_{\rm{gas}}$

### hydrated

solvated by water molecules

### hydration enthalpy

energy released when one mole of solute becomes completely hydrated

### hypertonic

at a pressure higher than the osmotic pressure of bodily fluids

### hypotonic

at a pressure lower than the osmotic pressure of bodily fluids

### ideal solution

solution for which $\Delta H_{\rm{soln}}=0$

### ion-dipole interaction

electrostatic interaction between ions and polar ends of molecules with permanent dipoles

### isotonic

at the same osmotic pressure as bodily fluids

### miscible

able to form a homogeneous (evenly distributed) mixture when added together in any proportion

### molality (m)

concentration expressed as the number of moles of a solute divided by the mass of solvent in kilograms

### molar solubility

molarity of a compound in a saturated solution

### molarity (M)

number of moles of a solute dissolved in 1 liter of solution

### mole fraction

concentration expressed as the moles of solvent divided by the total number of all moles in solution

### osmotic pressure

pressure needed to stop the flow of water through a semipermeable membrane

### saturation point

concentration at which no more solute dissolves in a solution for a given temperature and pressure

### semipermeable membrane

barrier through which certain types of particles can pass but not others

### solute

dissolved material in a solution

### solution

homogeneous mixture of two or more substances

### solvated

completely surrounded by solvent molecules

### solvent

substance that dissolves a material to form a solution

### strong electrolyte

ionic compound that dissociates completely into its component ions in solution

### supersaturated

condition in which a solution contains more solute than can be dissolved in the solution under normal circumstances

### Tyndall effect

phenomenon of light being scattered by a colloid

### unsaturated

condition in which more solute can be dissolved into the solution

### weak electrolyte

ionic compound that only partially dissociates into its component ions in solution