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Collision theory explanation

GCSE · Chemistry · CCEA · U2.3Rates of reaction — collision theory, factors, catalysts

Question

CCEA Unit 2

A student investigates the reaction between marble chips (CaCO₃) and dilute hydrochloric acid by measuring the volume of CO₂ produced over time.

(a) Using collision theory, explain why increasing the concentration of HCl increases the rate of reaction. [3 marks] (b) Explain why using powdered marble instead of lumps increases the rate. [3 marks] (c) The student repeats the experiment with excess acid but uses the same mass of marble chips. Sketch a graph showing the volume of CO₂ collected versus time for (i) large chips and (ii) small chips. Label both curves. [3 marks]

9 marks · take your time before peeking.

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Generated by TopMyGrade AI · cross-check official sources before relying on the mark-scheme phrasing.