1. Acids and Bases AS Unit F321, Module 1.1.3

2. What do you know already? 1.What are the particles in acids and alkali? 2.What’s the difference between an acid, an alkali and a base? 3.What are the names and formulae of common acids, alkalis and bases? 4.What are the reactions of acids with carbonates, bases and alkalis? 5.What happens to form an ammonium ion? 6.How would you work out the formula of a hydrated salt?

3. Common Acids and Alkalis Hydrochloric acid, HCl Sulfuric acid, H 2 SO 4 Nitric acid, HNO 3 Sodium hydroxide, NaOH Potassium hydroxide, KOH Aqueous ammonia, NH 4 OH (ammonium hydroxide)

4. Common bases Metal oxides eg. MgO, CaO Metal hydroxides eg. Mg(OH) 2 Ammonia, NH 3 Carbonates eg. K 2 CO 3, MgCO 3, CuCO 3 Hydrogen carbonates eg. NaHCO 3

5. Definitions An Acid releases H + ions in aqueous solution An alkali is a soluble base that releases OH - ions in aqueous solution A base readily accepts H + ions from an acid BRØNSTED-LOWRY THEORY ACIDproton donorHCl ——> H + (aq) + Cl¯(aq) BASEproton acceptor NH 3 (aq) + H + (aq) ——> NH 4 + (aq)

6. LEWIS THEORY ACIDlone pair acceptorBF 3 H + AlCl 3 BASElone pair donorNH 3 H 2 O LONE PAIR DONORLONE PAIR ACCEPTOR LONE PAIR DONORLONE PAIR ACCEPTOR

7. Strong Acids and Bases STRONG ACIDS completely dissociate (split up) into ions in aqueous solution e.g. HCl ——> H + (aq) + Cl¯(aq) MONOPROTIC1 replaceable H HNO 3 ——> H + (aq) + NO 3 ¯(aq) H 2 SO 4 ——> 2H + (aq) + SO 4 2- (aq) DIPROTIC 2 replaceable H’s STRONG BASES completely dissociate into ions in aqueous solution e.g. NaOH ——> Na + (aq) + OH¯(aq)

8. Weak Acids Weak acids partially dissociate into ions in aqueous solution e.g. ethanoic acid CH 3 COOH(aq) CH 3 COO¯(aq) + H + (aq)

9. Reactions of Acids 1.acid + metal  salt + hydrogen 2.acid + metal oxide  salt + water 3.acid + metal hydroxide  salt + water 4.acid + carbonate  salt + water + carbon dioxide 5.acid + hydrogen carbonate  salt + water + carbon dioxide 6.acid + ammonia  ammonium salt

10. Making Salts Hydrochloric acid  chlorides Nitric acid  nitrates Sulfuric acid  sulfates Ethanoic acid  ethanoates

11. What is the difference between hydrogen chloride and hydrochloric acid?

12. What else do I need to be able to do? Ionic equations Acid-Base titrations Explain the terms anhydrous, hydrated and water of crystallisation Calculate the formula of a hydrated salt from given % composition, mass composition or experimental data