Question

Write the name and general formula of a chain of hydrocarbons in which an addition reaction with hydrogen is possible. State the essential condition for an addition reaction. Stating this condition, write a chemical equation giving the name of the reactant and the product of the reaction.

Write the name and general formula of a chain of hydrocarbons in which an addition reaction with hydrogen can take place. Stating the essential conditions required for an addition reaction to occur, write the chemical equation giving the name of the reactant and the product of such a reaction.

Answer 1

Name and general formula of hydrocarbons undergoing addition reaction with hydrogen:

Name	General Formula
Alkene	CnH2n
Alkyne	CnH2n-2

Essential conditions required for the addition reaction to occur:-

• Multiple bonds (double and triple bonds) must be present between carbon atoms in the chain of hydrocarbon.
• Addition of hydrogen should be carried out in the presence of catalyst such as nickel or platinum.

Chemical Equation:-

Answer 2

The addition of hydrogen is possible in alkenes and alkynes. This is because of the presence of double and triple bonds, respectively. The general formula of alkenes is C_nH_2n and that of alkynes is C_nH_2n−2.

Conditions for addition reactions are

• Presence of an unsaturated compound, i.e. an unsaturated hydrocarbon.
• Presence of a species to be added to an unsaturated compound.
• Presence of a catalyst such as finely divided palladium or nickel.