Factors Affecting Solubility

Solubility Measures mass of a solute that can dissolve in a specific solvent at a certain temperature.

1. Polarity “Like Dissolves Like” Soluble Insoluble Insoluble Soluble NON POLAR POLAR Water Cyclohexane C6H6 CoCl2 I2 Sucrose (C12H22O11) POLAR Soluble Insoluble NON POLAR Insoluble Soluble POLAR Soluble Insoluble “Like Dissolves Like”

Sucrose has 8 polar OH groups able to form hydrogen bonds with water 1. Polarity Solutes dissolve in a solvent with similar forces of attraction Sucrose has 8 polar OH groups able to form hydrogen bonds with water

2. Molecule Size Molecules with small non-polar sections can be soluble in polar solvents miscible miscible miscible Decreasing solubility Effect of polar OH predominates Effect of non-polar portion predominates

3. Temperature Solubility of a solid solute in a liquid solvent usually increases with temperature

3. Temperature Solubility of most gases in most liquid solvents decreases with an increase in temperature

4. Pressure Increased pressure of a gas above a liquid solvent increases the solubility of that particular gas

ENERGY CHANGES IN THE SOLUTION PROCESS 3 Processes Solute separation, the particles must separate from one another this requires energy endothermic Solvent separation, the solvent particles must also separate from each other also endothermic Solute particles attract solvent particles releases energy exothermic.

Endothermic exothermic processes process The solution process overall can be either exothermic or endothermic depending on energy required for each process