The decomposition of a compound by heat in the absence of air is called as
The decomposition of a compound by heat in the absence of air is called as pyrolysis. When pyrolysis occurs in alkanes, the process is termed as cracking. The alkanes, on heating under high temperature or in the presence of a catalyst in the absence of air, are broken down into lower alkanes, alkenes and hydrogen.
2CH415000C−−−−→HC≡CH+3H2