Working with solutions Solutions and suspensions Suspension-a mixture in which particles can be seen and easily separated by settling or filtration Solution- a well mixed mixture

Solvents and solutes Solvent- a part of a solution present in the largest amount. Solute- a substance that is present in a solution in a smaller amount and dissolved by the solvent. Water as a solvent- water is called the universal solvent. Water is not the only solvent.

Particles in a solution Whenever a solution forms, particles of the solute leave each other and become surrounded by particles of the solvent. Ionic solids in water- positive and negative ions are attracted to polar water molecules. Molecular solids in water- break up into individual neutral molecules and are surrounded by water. Ionic compounds conducted electricity molecular compounds do not.

Concentration Dilute solution- only a little solute is dissolved in the water. Concentrated solution- more solute is dissolved in water.

solubility Solubility- a measure of how well a solute can dissolve in a solvent at a given temperature. Saturated solution- when you added so much solute that no more dissolves. Unsaturated solution- you can continue to dissolve more solute.

Changing solubility Two factors that effect solubility are temperature and type of solvent. Temperature- heating the solvent allows more solute to be dissolved. Solvents- polar compounds dissolve in polar solvent, non-polar compounds do not dissolve in polar solvents.

Effects of solutes on solutions Solutes lower the freezing points of a solvent. Solutes raise the boiling point of a solvent.

Describing acids and bases Properties of acids Sour taste Reacts with metals and carbonates Turns blue litmus red (indicator) Corrosive- eat away metals

Properties of bases Bitter taste Slippery feel Turns red litmus blue (indicator) Do not react with metals

Acids and bases in solution Acids and solution Hydrogen ion (H+)- an atom of hydrogen that lost its electron. An acid is any substance that forms hydrogen ions (H+) in water.

Bases in solution Hydroxide ion- polyatomic oxygen and hydrogen ion. (OH-) A base is any substance that forms hydroxide ions in water. A strong acid will produce more hydrogen ions than a weak one. A strong base will produce more hydroxide ions that a weak one.

Measuring PH PH is measure a scale of 0 – 14 with 0 being the most acidic and 14 being the most basic. Seven is neutral. Acid rain – normal rain equals 5.5, acid rain is as low as 3. Acid base reaction- neutralization- a reaction between a acid and a base who’s product is a salt.

Digestion pH Two types of digestion Mechanical digestion- tears, grinds, and mashes large food particles into smaller ones. Chemical digestion- breaks large molecules into smaller molecules. mouth= 7 Stomach= 2 Small intestine= 8