Solved UPSC CDS/OTA Question
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Q · Chemical EquationsMedium · 45s
Which of the following reactions is always accompanied by the release of energy?
TopicChemical Equations
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Combustion reactions are classic examples of exothermic reactions — they release energy in the form of heat and light. Photosynthesis and electrolysis absorb energy, and thermal decomposition generally requires heat input.
Final Answer: Option A - Combustion of fuels