Question

what is pyrolysis or cracking? explain with example.

Answer 1

Pyrolysis is a thermal decomposition of materials at elevated temperatures in an inert atmosphere such as a vacuum or nitrogen gas. It involves the change of chemical composition and is irreversible.
The word is coined from the Greek-derived elements pyro "fire" and lysis "separating".

Answer 2

Answer:

The decomposition of a compound by heat in the absence of air is called pyrolysis. When pyrolysis occurs in alkanes, the process is termed cracking.

For example:

Alkanes on heating under high temperature or in the presence of a catalyst in absence of air broken down into lower alkanes, alkenes and hydrogen.