1. © Oxford University Press 2009 7.1 Using Metals Metals in the periodic table Most elements are metals The elements on the left of the stepped line are metals.

2. © Oxford University Press 2009 7.1 Using Metals Find 3 essential properties of metals for water pipes Malleable Do not react with water or air Strong More information: Lead is no longer used for water pipes because it can make poisonous solutions. Metal choices… …copper or lead

3. © Oxford University Press 2009 7.1 Using Metals Find 4 essential properties of metals for saucepans Good conductors of heat Do not react with water Malleable Strong Metal choices… …copper, aluminium or stainless steel

4. © Oxford University Press 2009 7.1 Using Metals Find 4 essential properties of metals for jewellery Shiny Hard Malleable Do not react with water or air Metal choices… …gold, silver, platinum

5. © Oxford University Press 2009 7.1 Using Metals Find 3 essential properties of metals for electrical wiring Ductile Good conductor of electricity Do not react with water or air More information: Copper is a better conductor than aluminium Metal choices… …copper, aluminium

6. © Oxford University Press 2009 7.1 Using Metals Find 4 essential properties of metals for long- distance power cables Ductile Good conductors of electricity Low density Do not react with water or air More information: Copper is 3 times denser than aluminium Metal choices… …copper, aluminium

7. © Oxford University Press 2009 7.1 Using Metals Find 4 essential properties of metals for aeroplanes Low density Malleable Do not react with water or air Strong More information: Aluminium does not react with water or air because it forms a protective coating on its surface Metal choice… …aluminium

8. © Oxford University Press 2009 7.1 Using Metals Find 4 essential properties of metals for light bulb filaments Ductile Glow when hot Very high melting points (so they don’t melt when they glow) Good conductor of electricity More information: Tungsten has the highest melting point of all metals (3410 ºC) Metal choice… …tungsten

9. © Oxford University Press 2009 7.1 Using Metals Find 2 essential properties of metals for a tip- over switch Tip-over switches in electric heaters switch off the current if the heater falls over, so preventing fires. Good conductors of electricity Liquid at room temperature More information: Mercury is the only metal that is liquid at room temperature. Its melting point is -38.9 ºC and its boiling point is 357 ºC Metal choice… …mercury

10. © Oxford University Press 2009 7.1 Using Metals Find 8 properties that most metals have Strong Solid at room temperature (melting point above 25 ºC) Good conductor of electricity Good conductor of heat Shiny (at least when first cut) Malleable Ductile Hard

11. © Oxford University Press 2009 7.1 Using Metals But metals are not all the same…

12. © Oxford University Press 2009 7.1 Using Metals Extreme metals Melting points Highest – tungsten melts at 3410 ºC. Lowest – mercury melts at -38.9 ºC, so it is liquid at room temperature.

13. © Oxford University Press 2009 7.1 Using Metals Extreme metals Density Highest – iridium and osmium (22.5 g/cm³) (lead 11.3 g/cm³) Lowest – potassium (0.86 g/cm³) (aluminium 2.70 g/cm³) So a centimetre cube of iridium weighs 26 times as much as one of potassium!

14. © Oxford University Press 2009 7.1 Using Metals Extreme metals Reactions in water and air Don’t react at all – platinum and gold React violently – potassium, rubidium, caesium

15. © Oxford University Press 2009 7.1 Using Metals Metal patterns Different metals have many similarities… …but many differences In this unit you will… Look at some properties of different metals Find patterns in these properties Use the patterns to predict metal reactions