Organic Compounds Chemists observed that there were two types of substances. Those from non-living matter and those from living matter. They were classified into two categories which include inorganic substances and organic substances. Many similar properties were observed by the Chemists. Most inorganic substances were observed to change very little, if any, when heated. Also, organic substances were thought to be produced only by living organisms. Later in time organic substances were studied in greater detail. Chemists learned that nearly all organic compounds are made of chains and rings of carbon atoms. Chemists then learned to synthesize some simple organic c