1. Acids and bases

2. acids Always contain hydrogen. Always contain hydrogen. Strong or weak acids. Strong or weak acids. Common properties Sour Sour Gritty Gritty Corrosive Corrosive Blue litmus red Blue litmus red Neutralise bases Neutralise bases pH of less than 7 pH of less than 7

3. Bases Produce either OH - or O 2- ions. Produce either OH - or O 2- ions. Strong or weak bases. Strong or weak bases. Common properties Bitter Bitter Soapy Soapy Caustic Caustic Red litmus blue Red litmus blue Neutralise acids Neutralise acids pH of more than 7 pH of more than 7

4. indicators The pH scale: 0-14 The pH scale: 0-14 Lots of free hydrogen, low pH (acidic) Lots of free hydrogen, low pH (acidic) Few free hydrogen, high pH (basic) Few free hydrogen, high pH (basic) Indicators show the pH. Indicators show the pH. Some are precise: Universal Indicator Some are precise: Universal Indicator Others are not as precise: Litmus Paper Others are not as precise: Litmus Paper

5. neutralisation When an acid and base ‘cancel’ each other out, they become neutralised…. When an acid and base ‘cancel’ each other out, they become neutralised…. They create a neutral substance They create a neutral substance Neither acidic or basic Neither acidic or basic pH of 7 pH of 7

6. Neutralisation Reactions General equation: General equation: acid + base  salt + water Acid + hydroxides Acid + hydroxides Acid + oxides Acid + oxides Acids + carbonates Acids + carbonates

7. Acid + hydroxide Acid + hydroxide  salt + water Hydrochloric acid + sodium hydroxide  sodium chloride + water Hydrochloric acid + sodium hydroxide  sodium chloride + water Nitric acid + lithium hydroxide  lithium nitrate + water Nitric acid + lithium hydroxide  lithium nitrate + water Nitric acid + calcium hydroxide  calcium nitrate + water Nitric acid + calcium hydroxide  calcium nitrate + water

8. Acid + oxide Acid + oxide  salt + water Hydrochloric acid + calcium oxide  calcium chloride + water Hydrochloric acid + calcium oxide  calcium chloride + water Sulfuric acid + lithium oxide  lithium sulfate + water Sulfuric acid + lithium oxide  lithium sulfate + water Sulfuric acid + barium oxide  barium sulfate + water Sulfuric acid + barium oxide  barium sulfate + water

9. Acids + carbonates Acid + carbonate  salt + water + carbon dioxide (Acid + hydrogen carbonate  salt + water + carbon dioxide) Nitric + sodium  sodium nitrate + water + carbon Nitric + sodium  sodium nitrate + water + carbon acid carbonate dioxide acid carbonate dioxide Hydrochloric + ammonium  ammonium + water + carbon Hydrochloric + ammonium  ammonium + water + carbon acid carbonatechloride dioxide Sulfuric + sodium hydrogen  sodium + water + carbon Sulfuric + sodium hydrogen  sodium + water + carbon acidcarbonate sulfate dioxide

10. Acids + metals Not neutralisation. Not neutralisation. No water produced. No water produced. No base in the equation. No base in the equation. Magnesium + HCl

11. Acids + metals Acid + metal  salt + hydrogen Hydrochloric + magnesium  magnesium + hydrogen Hydrochloric + magnesium  magnesium + hydrogen acid chloride gas Sulfuric + magnesium  magnesium + hydrogen acid sulfate gas Sulfuric + magnesium  magnesium + hydrogen acid sulfate gas Nitric acid + calcium  calcium nitrate + hydrogen Nitric acid + calcium  calcium nitrate + hydrogen gas gas