3.5 - Metals

using a blast furnace reacting with more reactive material electrolysis

• tendency to become oxidised is linked to how reactive a metal is • metals higher up are less resistant to oxidation than • metals placed lower down which are more resistant to oxidation, reacts with water • position of the metal on the reactivity series determines the method of extraction

• extracted by ELECTROLYSIS of the molten chloride or oxide • large amounts of ELECTRICITY are required, which makes this an EXPENSIVE process

• extracted by heating with a reducing agent such as carbon or carbon monoxide in a BLAST FURNACE • cheap process as carbon is CHEAP and can also be a source of heat

• found as PURE elements

Potassium Sodium Lithium Calcium Magnesium Aluminium Zinc Iron Copper Silver Gold

aircraft bodies - high strength-to-weight ratio (low density) saucepans - very good conductor of heat and unreactive overhead electrical cables - very good conductor of electricity food cans - non-toxic, resistant to corrosion and resistant to acidic food stuffs

electrical wiring - very good conductor of electricity and ductile saucepans - very good conductor of heat, unreactive, malleable water pipes - unreactive (does not react with water), non-toxic and malleable

building material - good strength, malleable and ductile, relatively inexpensive catalyst - increases the rate of reaction without being used up

alloyed with - 0.25% carbon • car body panels and wiring • soft and malleable

alloyed with - 0.5-1.4% carbon • tools, e.g. chisels • hard

alloyed with - 20% chromium and 10% nickel • cutlery, sinks and chemical plants • strong and resistant to corrosion

a mixture of two or more metals or metal with a non-metal such as carbon e.g. steel is made from iron and carbon

• stronger and harder • resistant to corrosion or extreme temperatures • makes it more useful than pure metals

• pure metal has layers so the atoms can slide over more easily • alloy has different sized atoms which are randomly arranged which prevents layers sliding over

70% copper and 30% zinc

• outer electrons become ‘delocalised’ which means they are free to move throughout the whole structure • metals have a giant regular arrangement of layers of positive ions surrounded by a sea of delocalised electrons

salt + hydrogen __(s) + H2SO4 (aq) → __SO4 (aq) + H2 (g)

iron + water + oxygen ⟶ hydrated iron(III)oxide

Oxygen and water

a substance gains oxygen - lose electrons

a substance loses oxygen - gain electrons

what supplies the oxygen

removes the oxygen