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Chemical equilibrium — Question 20

QCAA 2025, Paper 1 · 1 mark

Q20 · 2025 · Paper 1Unclassified1 mark

QUESTIONS 19–20 Questions 19–20 refer to the reversible chemical reaction and enthalpy level diagram shown.

Chemistry question figure

QUESTION 20

Determine the activation energy (Ea) of the reverse reaction.

(A) 20 kJ mol−1

(B) 40 kJ mol−1

(C) 60 kJ mol−1

(D) 80 kJ mol−1

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