Question

Which of the following compounds will undergo an addition reaction?

• A. $C_3{H}_8$
• B. $C_2{H}_2$
• C. $C_3{H}_6$
• D. $C_4{H}_{10}$

Answer 1

Answer: (B), (C)

The correct options are
B $C_2{H}_2$
C $C_3{H}_6$

The reaction in which atoms combine with unsaturated carbon compounds to form saturated carbon compounds is called addition reaction. Butane and propane are saturated hydrocarbons and hence, they will not undergo addition reaction while propene and acetylene are unsaturated hydrocarbons which will undergo addition reaction.
For example, propene will undergo an addition reaction with chlorine to form 1, 2, Dichloropropane. $C{H}_{3}CH=C{H}_2\left(g\right)+C{l}_2\left(g\right)\to C{H}_{3}CHClC{H}_{2}Cl\left(g\right)$

Acetylene will undergo an addition reaction with hydrogen to form ethene.
$CH\equiv CH\left(g\right)+H_2\to C{H}_2=C{H}_2\left(g\right)$