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Question
Which of the following graphs represents exothermic reaction?
(a)

(b)

(c)

Options
(a) only
(b) only
(c) only
(a) and (b)
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Solution
(a) only
Explanation:
Exothermic reaction is a chemical reaction in which the enthalpy change is negative and energy is released in the form of light and heat.
As we all know, ΔH is negative.
Activation energy (forward reaction) – (backward reaction)
(Forward reaction) – Ea (backward reaction)
The product's exothermic energy exceeds the activation energy of the reactant.
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