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O-LevelChemistryRates of Reaction5070/12 · May/June 2022 · Q181 Mark

Which reaction is exothermic?

Acombustion of methane
Bcracking of hydrocarbons
Cdecomposition of water into hydrogen and oxygen by electrolysis
Dphotosynthesis in plants

✓ Correct answer

A: combustion of methane

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About this question

Topic
Rates of Reaction, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source
O-Level Chemistry, May/June 2022 Paper 1 Variant 2, question 18.

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