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Question
Which of the following can be decomposed by the action of light?
Options
NaCl
KCI
AgCl
CuCl
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Solution
AgCl
Explanation:
Silver chloride (AgCl) is highly sensitive to light and undergoes a photochemical decomposition reaction. When exposed to sunlight, it breaks down into grey silver metal and pungent chlorine gas.
\[\ce{2AgCl_{(s)} ->[Sunlight] 2Ag_{(s)} + Cl2_{(g)}}\]
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