Reactions
Checking your progress To make good progress in understanding science you need to focus on these ideas and skills. Describe what is meant by the term exothermic reaction, with examples.
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Explain the energy changes taking place during an exothermic reaction.
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Use energy-level diagrams to compare the energy in the reactants and products of exothermic reactions, explaining the energy changes in the particles.
Dr aft Ch Sam ap pl te r e
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Describe what is meant by the term endothermic reaction, with examples.
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Explain the energy changes taking place during an endothermic reaction.
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Use energy-level diagrams to compare the energy in the reactants and products of endothermic reactions, explaining the energy changes in the particles.
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Describe the endothermic reaction that takes place in a cold pack.
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Plan an investigation including selecting a range of values and intervals.
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Design a suitable results table and draw a suitable graph to investigate a correlation.
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Describe what a catalyst is and give examples.
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Interpret data to explain how a catalyst affects a reaction.
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Explain how a catalyst works.
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Identify changes during a reaction, relate these to reactants and products.
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Make accurate observations, explain them using a simple model and a word equation and explain differences between chemical and physical changes in terms of atoms.
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Explain observations using word equations, relate chemical symbols to a simple particle model and use the correct terms and simple models to explain the differences between chemical and physical changes.
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AQA KS3 Science Student Book Part 2: Reactions – Chemical energy and Types of reaction