III. Solvation + Solutions

A. What is a Solution? Solution – uniform mixture that may contain solids, liquids, or gases Consists of a solute and a solvent Solute – The substance that is dissolved Solvent – The substance that does the dissolving

B. Common Types of Solutions Solute Solvent Solid Liquid Gas

C. Characteristics of Solutions Soluble – able to dissolve Insoluble – unable to dissolve Immiscible – two liquids that do not mix together (ex. Oil + water) Miscible – two liquids that are soluble in each other (ex. water + acetone)

A. Solvation Solvation – the process of surrounding solute particles with solvent particles to form a solution Leads to dissolution (dissolving) of solute Caused by constant, random motion of molecules Aqueous solution – a solute that is dissolved in water

B. Rate of Solvation Increase the rate of solvation Stirring Increase surface area Increase temperature Increase pressure (for gases only)

C. Saturation vs. Unsaturation Unsaturated solution – solution that is still able to dissolve particles Saturated solution – solution that has dissolved the maximum amount of particles Supersaturated solution – solution that has dissolved more than the maximum amount of particles Needs to be at high temperatures to achieve

D. Solubility Solubility – the amount of substance that can be dissolved in a given solvent Usually expressed in grams of solute per liter of solvent How to increase solubility (how to increase how much can dissolve)? Increase temperature (except for gases dissolved) Increase pressure (gases only)