1. 1. Write down everything you can remember about: 2. Do you remember any properties of an acid?

2. Lesson 4 Learning Objectives: Describe the test for hydrogen (H) ions using acid/base indicators Describe and explain the typical reactions of acids, using balanced formulae equations

3. A quick look at acids … What do all acids have in common? H SO 4 H NO 3 Cl H H ALL acids contain HYDROGEN – this is important!

4. NameFormula Hydrochloric acid Ethanoic Acid Nitric Acid Sulfuric Acid HCl CH 3 COOH HNO 3 H 2 SO 4

5. INDICATORS are DYES that CHANGE COLOUR depending upon whether they are in ACIDIC or ALKALINE CONDITIONS. Litmus Red in acid Blue in alkali Methyl orange Red in acid Yellow in alkali Universal indicator has a range of colours and a pH number to go with the colours

6. 1.Add 2cm depth of the acid to a test tube. 2.Add a small amount of the three metals – magnesium ribbon (1–2 cm), zinc granules and copper turnings (half a spatula) – each to a separate test tube of the acid. 3.If a gas is produced test it with a lighted splint. 1.Add half a spatula of sodium carbonate to a separate test tube of the acid, and observe what happens. 2.If a gas is produced, test it by bubbling it through limewater. Metal + metal carbonates Metal + Acid

7. K + HCl  KCl + H 2 K 2 + H 2 SO 4  K 2 SO 4 + H 2 K + HNO 4  KNO 4 + H 2 Ca + HCl  CaCl + H 2 Ca 2 + H 2 SO 4  Ca 2 SO 4 + H 2 Ca + HNO 4  CaNO 4 + H 2 …and so on!

8. H SO 4 H Mg

9. HCl H Mg ?

10. H SO 4 H Na ?

11. Any metal! It could be a +1 or +2 cation (positive ion) eg Na + or Cu 2+ This is a CO 3 2- ion

12. H SO 4 CuC O O O H

13. H SO 4 NaC O O O H ?

14. HClC O O O H Na ?

15. HClC O O O H Cu ?

16. SALTS When an acid reacts with a metal or a metal compound they make A SALT. Salts are a specific group of chemicals –they are all NEUTRAL (not acidic or alkaline) –they are made up of a metal part and the NON-HYDROGEN part of an acid.

17. sulphates chlorides nitrates If you use these acids… H SO 4 H NO 3 Cl H H H 2 SO 4 HCl HNO 3

18. What type of salts do you think the following would form? –carbonic acid –stearic acid –phosphoric acid

19. Practice 1.Nitric acid + potassium  2.Magnesium + hydrochloric acid  3.Iron carbonate + sulphuric acid  4.Zinc carbonate + hydrochloric acid  5.Zinc + sulphuric acid  6.Nitric acid + magnesium  7.Aluminium + hydrochloric acid  8.Potassium carbonate + nitric acid 

20. Writing a general equation. Metal + Acid  Salt + hydrogen Metal Carbonate + Acid  carbon dioxide + salt + water

21. Predictions … What do you think might be formed in the following? hydrochloric acid and sodium hydroxide? potassium hydroxide and sulphuric acid? magnesium oxide and hydrochloric acid?