CAIE A Level Chemistry 9701 · Reaction kinetics

Reaction kinetics: describe question

Describe7 marksChallenge

In the reaction between $\ce{H2(g)}$ and $\ce{I2(g)}$ , the activation energy is 171 kJ mol⁻¹. Explain what is meant by activation energy and, with reference to the Boltzmann distribution, why raising the temperature greatly increases the rate of this reaction.

How this question is marked

7 marks, so the mark scheme is looking for about 7 separate creditworthy points. Making the same point twice in different words earns it once.

Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.

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