Which of following is NOT a redox reaction?

Which of following is NOT a redox reaction?
  1. $\mathrm{CH}_3 \mathrm{CHO}+\mathrm{Cu}(\mathrm{OH})_2 \longrightarrow \mathrm{CH}_3 \mathrm{COOH}+\mathrm{Cu}_2 \mathrm{O}$
  2. $\mathrm{SnCl}_4+\mathrm{FeCl}_2 \longrightarrow \mathrm{FeCl}_3+\mathrm{SnCl}_2$
  3. $\mathrm{H}_2 \mathrm{SO}_4+\mathrm{Ca}(\mathrm{OH})_2 \longrightarrow \mathrm{CaSO}_4+\mathrm{H}_2 \mathrm{O}$
  4. $\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}+[\mathrm{O}] \longrightarrow \mathrm{CH}_3 \mathrm{CHO}+\mathrm{H}_2 \mathrm{O}$

Solution

$\mathrm{H}_2 \mathrm{SO}_4+\mathrm{Ca}(\mathrm{OH})_2 \longrightarrow \mathrm{CaSO}_4+\mathrm{H}_2 \mathrm{O}$ Acid Base It is Acid-Base Reaction or double-displacement reaction.

Asked in: MHT CET 2021 (24 Sep Shift 2)

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