Hydrocarbons – Solutions

1) How do you account for the formation of ethane during chlorination of methane?

Solution

The formation of ethane during the chlorination of methane occurs due to free radical chain mechanism. The reaction begins with the cleavage of Cl-Cl, forming free chlorine radicals. The free chlorine radicals attack methane molecules, and break down the C-H bond to generate methyl radicals. Hence, methyl free radicals and chlorine free radicals set up a chain reaction. The formation of ethane is a result of the termination of chain reactions taking place because of the combination of two methyl free radicals.

2) An alkene ‘A’ contains three C-C, eight C-H s bonds and one C-C p bond. ‘A’ on ozonolysis, gives two moles of an aldehyde of molar mass 44 u. Write IUPAC name of ‘A’.

Solution

The alkene (A) contains three C-C bonds and one C-C double bond, and on ozonolysis , it gives two moles of the same aldehyde, the position of the double bond should be on the second and third C- atoms.