Topic 4 – Chemical changes

Electrolysis

4.3.1 The process of electrolysis Electrolysis When ionic substance is molten (electrolyte) Ions move freely & pass electric current      +ve ions to move to -ve electrode (cathode)       -ve ions to move to +ve electrode (anode) Ions are discharged at electrodes...

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Reactivity of metals

4.1.1 Metal oxides Metal oxides Metal(s) + oxygen(g) → metal oxides(s) OIL RIG Oxidation is loss of electrons, gain of O2 Reduction is gain of electrons, loss of O2 (using carbon) 4.1.2 The reactivity series Reactivity series – need to memorize Please send lions,...

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Reactions of acids

Important formulae Acid + alkali / base → salt + water Acid + metal → salt + hydrogen Acid + metal oxide → salt + water Acid + metal hydroxide → salt water Acid + metal carbonate → salt + water + carbon dioxide 4.2.1 Reactions of acids with metals (Reactivity: see...

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