Lesson 10: Oxidation and metals Y9 Chemistry Unit Lesson 10: Oxidation and metals

Lesson Objectives List the properties of metals and discuss why only some are used for roofs (p.56-7) describe how metals oxidise, tarnish and corrode...reactivity with O2   (p.68-9) write word equations for chemical reactions of metals in air (p.57)

Properties of Metals Physical state Melting point Boiling point usually solid at room T Melting point usually high Boiling point Conduction of heat and electricity good

Properties of Metals Flexibility Malleability Ductility Oxides Rigid when thick, bendy when thin Malleability Can be hammered or rolled without cracking Ductility Can be pulled out into wires Oxides Metal oxides are bases (or alkali when dissolved in water)

Vocabulary Tarnish: lose or cause to lose lustre, especially as a result of exposure to air or moisture Corrode: the gradual destruction of materials (usually metals) by chemical reaction with their environment.

Reaction of metals with oxygen Metals used for buildings react slowly with oxygen Some metal oxides are very pretty (copper-green)

Reaction of metals with oxygen Gold- very expensive it does not react Titanium- expensive oxide is similar in colour to original metal Zinc- cheapest oxide layer is paler than original metal Copper – medium price- turns green

Word equations Metal + oxygen  metal oxide Titanium + oxygen  titanium dioxide Zinc + oxygen  zinc oxide Copper + oxygen  copper(II) oxide

Task Read page 55 in your booklet and Compete worksheets P.26- W.S. 44 Metals and non-metals p.32- 9Fb4 Reactions with Oxygen and Heat Read the descriptions of the reactions Make a chart in your notebook with the headings METAL REACTION organize the metals from the most reactive to the least reactive giving the description beside it