Question

Which of the following compounds decolourises Baeyer's reagent?

• A. $C_2{H}_6$
• B. $C_3{H}_8$
• C. $C_2{H}_4$
• D. $C_3{H}_{7}OH$

Answer 1

The correct option is C $C_2{H}_4$

Baeyer's reagent is an alkaline solution of potassium permanganate. It is used for the detection of unsaturation in the compound i.e. to test the presence of double or triple bond. In presence of unsaturation baeyer's reagent is decolorised.
Therefore $C_2{H}_4$ will decolorise the baeyer's reagent.