Since this reaction takes place by free radical mechanism. Hence, there is a possibility of formation of ethane.
\(\mathop {\mathop C\limits^. {H_3} + \mathop C\limits^. {H_3}}\limits_{{\rm{Methyl free radicals}}} \to \mathop {C{H_3} - C{H_3}}\limits_{{\rm{Ethane}}} \)