O-LevelChemistryRates of Reaction5070/11 · Oct/Nov 2023 · Q151 Mark

Hydrogen and bromine react to form hydrogen bromide. H2 + Br2 → 2HBr Bond energy data is given in the table. bond, bond energy in kJ/mol H-H, 436 Br-Br, 193 H-Br, 366 What is the enthalpy change, ∆H, for this reaction?

A-263 kJ/mol

B-103 kJ/mol

C+103 kJ/mol

D+263 kJ/mol

✓ Correct answer

B: -103 kJ/mol

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Topic: Rates of Reaction, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source: O-Level Chemistry, Oct/Nov 2023 Paper 1 Variant 1, question 15.

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