1. Reactivity of Metals

2. The reactivity series is the list of elements (Mainly Metals) in order of decreasing reactivity

3. The Reactivity Series The Reactivity Series lists metals in order of reactivity: Potassium Sodium Calcium Magnesium Aluminium Carbon Zinc Iron Lead Copper Silver Gold

4. The reactivity of metals is described as how easily an atom loses an electron For instance potassium is extremely reactive because it has only one valence electron, so it is very easy to lose it forming a positive ion.For instance potassium is extremely reactive because it has only one valence electron, so it is very easy to lose it forming a positive ion. On the other hand, copper is a weakly reactive metal because it has more valence electrons so it is harder for it to become a positive ion. On the other hand, copper is a weakly reactive metal because it has more valence electrons so it is harder for it to become a positive ion.

5. Reactions of metals with oxygen When a metal reacts with oxygen it will form a METAL OXIDE.This is what happens when a metal rusts.We can make this reaction happen quicker by burning the metal. METAL+OXYGENMETAL OXIDE

6. Reactions of metals with oxygen METAL+OXYGENMETAL OXIDE Copy and complete the following reactions: Magnesium + oxygen Copper + oxygen Calcium + oxygen Iron + oxygen

7. 07/03/12 Reactions of metals with water When a metal reacts with water hydrogen is always given off.The other product will be either a metal hydroxide or a metal oxide. METAL+WATER(Steam) METAL + WATER(Cold water|) METAL OXIDE + HYDROGEN METAL HYDROXIDE + HYDROGEN

8. 07/03/12 Reactions of metals with water Copy and complete the following reactions: Sodium + water Potassium + water Calcium + water Iron + steam METAL+WATER METAL + WATER METAL OXIDE + HYDROGEN METAL HYDROXIDE + HYDROGEN

9. Reactions of metals with acids When a metal reacts with an acid it gives off hydrogen (which can be “popped” using a lit splint).The other product is a salt. METAL+ACIDSALT + HYDROGEN HOW VIGOROUSLY A METAL REACTS WITH A ACID ITS POSITION IN THE REACTIVITY SERIES!

10. 07/03/12 Reactions of metals with acids METAL+ACIDSALT + HYDROGEN E. g: magnesium + hydrochloric acidmagnesium chloride + hydrogen Copy and complete the following reactions: Calcium + hydrochloric acid Zinc + hydrochloric acid Iron + hydrochloric acid Lithium + sulphuric acid

11. MAGNESIUM+HCL ZINC+HCL IRON + HCL

12. Displacement reactions A displacement reaction is one where a MORE REACTIVE metal will DISPLACE a LESS REACTIVE metal from a compound. For example, if you drop some magnesium into copper sulphate a reaction will happen because magnesium is more reactive than copper, so the reaction is: Magnesium + copper sulphatecopper + magnesium sulphate However, if you drop some copper into magnesium sulphate NOTHING will happen.

13. Displacement reaction involving metal oxides EX:-Reaction between Mg and CuO a. Observation: At the end of the reaction, traces of a brown (red) solid are left. b. Interpretations: Copper metal is formed during the reaction. Magnesium metal is capable of displacing copper from copper oxide as it is more reactive. Chemical equation : Mg (s) + CuO (s)  Cu (s) + MgO (s) Displacement reactions examples

14. Displacement reaction involving metal salts EX:-Reaction between Mg and CuSO4 a. Observation: At the end of the reaction, traces of a brown (red) solid are left at the bottom of the beaker and the solution turns colorless. b. Interpretations: Copper metal is formed during the reaction. Magnesium metal is capable of displacing copper from copper sulfate as it is more reactive. Chemical equation : Mg (s) + CuSO 4 (aq)  Cu (s) + MgSO 4 (s) Displacement reactions examples

15. 07/03/12 Displacement reactions SO 4 MgCu MagnesiumCopper sulphate The magnesium DISPLACES the copper from copper sulphate SO 4 MgMg Magnesium sulphate Cu Copper A displacement reaction is one where a MORE REACTIVE metal will DISPLACE a LESS REACTIVE metal from a compound.

16. Example 1: Extracting metals Very few metals exist uncombined in the Earth's crust. Most metals are found in the form of compounds called ores. These compounds are often oxides. Metals can be extracted from their oxides by displacement reactions  The cheapest and most efficient way of doing this is to use carbon to react with the metal oxide. Iron is extracted by heating iron ore with carbon in blast furnace. One reaction that takes place is the reaction between iron(III) oxide and carbon: Iron(III) oxide + carbon → Iron + carbon dioxide 2Fe 2 O 3 (s) + 3C(s) → 4Fe(l) + 3CO 2 (g) In this reaction, Carbon is more reactive than Iron so it displaces it from its Oxide. In this reaction, Carbon is more reactive than Iron so it displaces it from its Oxide. Displacement reactions applications:

17. 07/03/12 The Blast Furnace 1) HAEMATITE (iron ore), limestone and coke (carbon) are fed in here 2) Hot air is blasted in here 3)The carbon reacts with oxygen from the air to form carbon dioxide. 4)The carbon dioxide reacts with more carbon to form carbon monoxide 6) Molten slag (waste) is tapped off here 5) Carbon monoxide reduces iron oxide to iron.The molten iron is tapped off here Iron oxide + carbon monoxideiron + carbon dioxide

18. Example 2: Thermite Reaction The blast furnace is used to produce iron on a large scale. Sometimes, it is necessary to produce a small amount of iron more quickly, for example if railway workers need to produce molten metal to fix a broken rail. The thermite reaction uses aluminum powder and iron(III) oxide. When ignited, the mixture reacts vigorously because of the large difference in reactivity between aluminum and iron. The heat produced in the reaction melts the iron produced. Iron(III) oxide + aluminum → iron + aluminum oxide Fe 2 O 3 (s) + 2Al(s) → 2Fe(l) + Al 2 O 3 (s) In this reaction, Aluminum is more reactive than Iron  Aluminum displaces Iron from Iron(III) oxide. Displacement reactions applications:

19.  THE POSITION OF THE METALS CAN BE PREDICTED BY CARRYING OUT REACTIONSUSING THE REACTIVITY SERIES, I.E, WHETHER A METAL BELONGS TO MOST REACTIVE METALS, MODERATE REACTIVE METALS OR THE LEAST REACTIVE METALS.  YOU CAN MAKE PREDICTIONS ABOUT THE REACTIONS OF UNFAMILLIAR METALS IF YOU KNOW THEIR POSITIONS IN THE REACTIVITY SERIES EX :-a)Use the reactivity series to predict whether manganese would react with copper( ǁ ) sulfate solution

20. Complete the following reactions: Lithium + water Lithium + hydrochloric acid Silver + oxygen Magnesium + sulphuric acid Potassium + oxygen Aluminium + oxygen Manganese + water Sodium + sulphuric acid Lithium + oxygen Nickel + hydrochloric acid

21. Complete the following reactions: Lithium + water Lithium + hydrochloric acid Silver + oxygen Magnesium + sulphuric acid Potassium + oxygen Aluminium + oxygen Manganese + water Sodium + sulphuric acid Lithium + oxygen Nickel + hydrochloric acid Lithium hydroxide + hydrogen Lithium chloride + hydrogen Silver oxide Magnesium sulphate + hydrogen Potassium oxide Aluminium oxide Manganese oxide + hydrogen Sodium sulphate + hydrogen Lithium oxide Nickel chloride + hydrogen

22. An example question on reactivity Metal Reaction with dilute acid Reaction with water Reaction with oxygen A B C D E

23. An example question on reactivity Metal Reaction with dilute acid Reaction with water Reaction with oxygen A Some reactionSlow reactionBurns brightly B No reaction Reacts slowly C No reaction D Violent reactionSlow reactionBurns brightly E Reasonable reaction Reacts with steam only Reacts slowly

24. Some example reactions… 07/03/12 ReactionPredictionObservations Zinc + copper sulphate Zinc + lead nitrate Copper + lead nitrate Copper + silver nitrate Extension work – write down the equations for these reactions

25. Some example reactions… ReactionPredictionObservations Zinc + copper sulphateReaction DID happen Zinc + lead nitrateReaction DID happen Copper + lead nitrateReaction DID NOT happen Copper + silver nitrateReaction DID happen Extension work – write down the equations for these reactions

26. Extracting Metals Some definitions: A METAL ORE is a mineral or mixture of minerals from which it is “economically practical” to extract some metal. Most ores contain METAL OXIDES (e.g. rust = iron oxide). To “extract” a metal from a metal oxide we need to REDUCE the oxygen.This is called a REDUCTION reaction.