# 3: Solutions

• 3.1: Introduction to Solutions
Solutions are composed of a solvent (major component) and a solute (minor component). Concentration is the expression of the amount of solute in a given amount of solvent and can be described by several qualitative terms. Solubility is a specific amount of solute that can dissolve in a given amount of solvent. "Like dissolves like" is a useful rule for deciding if a solute will be soluble in a solvent.
• 3.2: Units of Concentration
Quantitative units of concentration include molarity, molality, mass percentage, parts per thousand, parts per million, and parts per billion.
• 3.3: Dilutions
Calculate the new concentration or volume for a dilution or concentration of a solution.
• 3.4: Concentrations as Conversion Factors and Solution Stoichiometry
Know how to apply concentration units as conversion factors.
• 3.5: Colligative Properties
Certain properties of solutions differ from those of pure solvents in predictable ways.
• 3.6: Osmosis
Fish cells, like all cells, have semipermeable membranes. Eventually, the concentration of "stuff" on either side of them will even out. A fish that lives in salt water will have somewhat salty water inside itself. Put it in freshwater, and the freshwater will, through osmosis, enter the fish, causing its cells to swell, and the fish will die. What will happen to a freshwater fish in the ocean?