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  • Chemical changes

    • Acids and alkalis - Edexcel

      Indicators are used to determine if a solution is acidic or alkaline. Acids react with metals, bases and carbonates to produce salts. Neutralisation is the reaction between an acid and a base.

    • Salts - Edexcel

      Soluble salts can be made by reacting acids with soluble or insoluble reactants. Titration must be used if the reactants are soluble. Insoluble salts are made by precipitation reactions.

    • Electrolysis - Edexcel

      Electrolysis involves using electricity to break down electrolytes to form elements. The products of electrolysis can be predicted for a given electrolyte. Copper can be purified using electrolysis.

    • Sample exam questions - chemical changes - Edexcel

      Understanding how to approach exam questions helps to boost exam performance. Question types will include multiple choice, structured, mathematical and practical questions.

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