15.1 Water and Its Properties

• The high surface tension and low vapor pressure of water are the results of hydrogen bonding.
• The structure of ice is a regular open framework of water molecules held together by hydrogen bonds and arranged like a honeycomb.
• Molecules in liquid water are packed closer together than they are in ice.

15.2 Homogeneous Aqueous Systems

• In a solution, a solvent dissolves the solute. The solute becomes dispersed in the solvent.
• In the dissolving process, individual solute ions break away from the crystal. Solvent molecules surround the negatively and positively charged ions in a process called solvation and the ionic crystal dissolves.
• All ionic compounds are electrolytes because they dissociate into ions and thus can conduct electricity.
• The formula of a hydrate consists of the formula of the ionic salt followed by a dot and the number of water molecules associated with one formula unit of the salt.

15.3 Heterogeneous Aqueous Systems

• A suspension differs from a solution because the component particles of a suspension are much larger and do not stay suspended indefinitely.
• Colloids have particles smaller than those in suspensions and larger than those in solutions.