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Question
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Fe + S ⟶ FeS.
HCl + NaOH ⟶ NaCl + H2O
CuSO4 + Zn ⟶ ZnSO4 + Cu
\[\ce{CaCO3 ->[\Delta]CaO + CO2}\]
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Solution
\[\ce{CaCO3 ->[\Delta]CaO + CO2}\] is a decomposition reaction.
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