. . "Specifically, examples of carbon containing compounds include compounds represented by the formula Cn H2n+2 (n is a natural number) such as CH4, C2 H6, C3 H8, C4 H10, etc., compounds represented by Cn H2n (n is a natural number) such as C2 H4, C3 H6, C4 H8, etc., and compounds such as C2 H2, C6 H6, etc." . .