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Question
Give one example in the case where supplying energy [given below] is necessary for a chemical reaction.
Light energy
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Solution
Light Energy:
In presence of light – the molecules of the reactants absorb light energy and collide swiftly and react rapidly.
Example:
Photosynthesis in plants:
Plants manufacture food [glucose] from carbon dioxide and water – in the presence of chlorophyll [green pigment in plants] and sunlight.
\[\ce{Carbon dioxide + water ⇌[chlorophyll][sunlight] glucose + oxygen}\]
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