Solutions

What is a solution? A solution is a mixture of substances that appear the same throughout. (homogeneous) Solutes are dissolved in solvents. A solvent is the substance in greater amount A solute is the substance in the smaller amount.

Solutions are physical changes Physical or Chemical? Solutions are physical changes They can be reversed, and No NEW substances are being made.

Water in air (humidity) Types of solutions Solutions can be in any of the 3 phases: Solute Solvent Example Gas air Liquid CO2 in soda Water in air (humidity) Lemon juice in water solid Pastry dough Solid NaCl in H2O alloys

The Solution Process A solute dissolves in a solvent. “like dissolves like”  the substances must be dissolvable in each other.

Dissolvable  What is Solubility? The amount of a substance that can be dissolved in a solvent is called solubility. Solubility depends on the nature of the substances both solvent and solute. Solubility of substances can be compared by measuring.

Dissolvable  What is Solubility? Solubility is the mass of solute that can be dissolved in 100g of water under a given set of conditions (temperature and pressure).

Solubility Rules “Like dissolves Like” This means, ionic compounds will dissolve other ionic compounds. Polar substances (partially charged covalent compounds) dissolve other polar substances. Nonpolar substances dissolve other nonpolar susbsances.

Water Water is known as the Universal Solvent This is because it is POLAR Oxygen — Hydrogen Hydrogen + +

How to change solubility Increase Solid into Liquid Gas into Liquid Stirring Grinding Temperature Pressure N/A

How to change solubility Increase Solid into Liquid Gas into Liquid Stirring Grinding Temperature Pressure N/A N/A

Gas Solubility the Effects of Pressure

The Effects of Solutes All solute particles – affect the physical properties of the solvents Adding solutes lowers the freezing point of the solvent Adding solutes raises the boiling point of the solvent