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Question
Select the most appropriate option.
Which of the following reactions is exothermic?
Options
H2(g) → 2H(g)
C(s) → C(g)
2Cl(g) → Cl2(g)
H2O(s) → H2O(l)
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Solution
2Cl(g) → Cl2(g)
Hint:
Bond is formed between two Cl atoms and hence, energy is released.
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