1. Last lesson 2g) Hydrogen

2. acid + metal salt + hydrogen Hydrochloric acid + magnesiummagnesium chloride + hydrogen Nitric acid + ironiron nitrate + hydrogen Sulphuric acid + zinc zinc sulphate + hydrogen In general, hydrochloric acid makes a chloride, nitric acid makes a nitrate, and sulphuric acid makes a sulphate. “salts”

3. Preparation of hydrogen

4. Combustion of hydrogen 2H 2 + O 2 2H 2 O

5. Test for water Cobalt chloride paper turns from blue to pink

6. Pure water? Boils at 100°C

7. Hydrogen and chlorine H 2(g) + Cl 2(g) 2HCl (g) Hydrogen chloride gas (covalent) dissolves in water to from hydrochloric acid (H + + Cl - )

8. Today’s lesson h) The transition metals - iron and copper

9. A treasure hunt!

10. 1. Iron + steam iron(III) oxide + hydrogen. 2Fe (s) + 3H 2 O (g) Fe 2 O 3(s) + 3H 2(g)

11. 2. Iron wool heated to glowing red reacts vigorously with chlorine gas in a flask. The product is red-brown solid iron(III) chloride 2Fe + 3Cl 2 2FeCl 3

12. 3. Iron ions in solution will react with hydroxide ions to form iron hydroxides which are insoluble and very coloured Fe 2+ (aq) + 2OH - (aq) Fe(OH) 2(s) (“dirty green”) Fe 3+ (aq) + 3OH - (aq) Fe(OH) 3(s) (“rusty brown”)

13. 4. Copper will dissolve in concentrated nitric acid to form copper nitrate and brown nitrogen dioxide gas Cu(s) + 4HNO 3 (aq) Cu(NO 3 ) 2 (aq) + 2NO 2 (g) + 2H 2 O(l)

14. 5. copper(II) oxide is a base (does not dissolve in water) copper hydroxide is pale blue and is formed when sodium hydroxide is added to a copper salt. It us used as a test for copper.

15. 6. Anhydrous copper sulphate is white and hydrated copper sulphate is blue (reversible) Copper carbonate decomposes at high temperatures to form copper oxide and carbon dioxide. CuCO 3 (s) → CuO (s) + CO 2 (g)

16. 7. Copper chloride is light green There are copper(I) compounds such as copper(I) oxide

17. 8. copper(II) ions react with ammonia to form the following complex ion (copy carefully!) [Cu(H 2 O) 2 (NH 3 ) 4 ] 2+

18. 9. Copper and iron are typical transition metals Variable valency (ions with different charges) Coloured compounds Metals and their compounds make good catalysts Properties of variable valency Typical metals (high m.p., dense, conduct, ductile, malleable etc.)