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Which one of the following is a reduction reaction?

Options

  1. A2 Mg ( s )+ O ₂( ~g ) 2 MgO ( s )
  2. BS ( s )+ O ₂( ~g ) SO ₂( ~g )
  3. C2 HgO ( s ) heat 2 Hg (l)+ O ₂( ~g )
  4. DMg ( s )+ S ( s ) MgS ( s )

Correct answer

C. 2 HgO ( s ) heat 2 Hg (l)+ O ₂( ~g )

Step-by-step solution

Mercuric oxides got reduced to mercury and its oxidation number changes from +2 to 0 . Whereas in other reaction are showing oxidation reaction.

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