While each of the three elements have two carbon molecules inside of them, each of them are different as the atoms inside of them are single, double, and triple bonded. The best example is with ethane in which each of the two carbon atoms are triple bonded to three hydrogen atoms. The suffixes of the elements are vital in letting a person know exactly what their atomic makeup and structure actually is.
This also gives credit as to actually how they bond and how their carbon atoms act. This is a known thing that works all throughout organic chemistry. The bonding is what gives the elements its life and structure and how they are able to interact with other atoms and elements. It certainly is one of those things that makes organic chemistry a very amazing science and one that is being studied and innovated for a very long time.
The two (2) carbons are single, double, and triple bonded with each other in ethane, ethene, and ethyne, respectively.-under most circumstances and certainly in virtually all natural states, a carbon atom seeks to form four (4) covalent bonds. other configurations are not energetically favorable. hydrogen can only form single covalent bonds. in the case of ethane, each carbon atom is bonded to three (3) hydrogen atoms, and the other carbon atom. in ethene and ethyne, the carbon atoms are double or triple bonded to each other. the -ane, -ene, -yne suffixes are used throughout organic chemistry and biology, and are useful for understanding the structure of carbon molecules.