The newest 5 of 5 written questions. Open one to see it on the real paper.
Fig. 5.1 shows the incomplete reaction pathway diagram for an endothermic reaction. Complete Fig. 5.1. Include: • • • the energy level of the products a labelled arrow to show the activation energy, E a a labelled arrow to show the overall energy change of the reaction. energy reactants progress of reaction
See it on the paper →State the name of the energy change represented by arrow A.
See it on the paper →Describe what happens during the energy change represented by arrow A. Use ideas about bonds in your answer.
See it on the paper →Draw an arrow on Fig. 8.2 to show the activation energy for the reaction. Label this arrow A.
See it on the paper →On Fig. 2.1 draw a double headed arrow ( ) to show the activation energy for this reaction.
See it on the paper →Most candidates gained partial credit for drawing a reaction profile with the energy of the products higher than the energy of the reactants (endothermic). Some candidates labelled an arrow to identify the activation energy. Common errors included a double arrow for the overall energy change (this should indicate direction as well as magnitude) and also arrows that do not completely fill the space...
— Examiner report, May/June 2025, 0653/42 Q5(a)(iii) (Cambridge)
Most candidates were familiar with the term activation energy.
— Examiner report, February/March 2023, 0653/42 Q5(b)(ii) (Cambridge)
Some candidates correctly stated that the energy change A involves the breaking of bonds. The most common mistake was to suggest that bonds were being formed.
— Examiner report, February/March 2023, 0653/42 Q5(b)(iii) (Cambridge)
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