The Life and Science of Percy Julian
Activities and Readings
2B (Reading)

What Is Organic Chemistry?

Words are funny things. A word that means one thing to one person might mean something completely different to another person. In the United States the word football refers to a game played with an oval-shaped ball that players pass with their hands or hold with their hands while they run with it. In England football refers to a game played with a round ball that players kick with their feet. (In the United States people call this game soccer.)

The word organic is another word that means different things to different people. To many people organic means “natural.” For example, gardeners sometimes talk about using organic fertilizer. What they mean is that they’re putting something natural like compost or manure on their plants instead of human-made, or synthetic, fertilizers.

Organic means something completely different to chemists. In chemistry organic means “carbon-based.” To a chemist, an organic compound is any compound that contains carbon. That is, an organic compound is any compound whose molecules contain carbon atoms. All living things are made of compounds containing mostly carbon, so lots of things that are “organic” to a gardener are also “organic” to a chemist.

Of course, there are many carbon compounds that are human-made, or synthetic. To chemists, these are organic compounds too. Plastics are organic, and so are most synthetic wonder drugs, as far as chemists are concerned. They are organic because they are carbon-based. Chemists would even say most of the synthetic fertilizers, the ones that “organic” gardeners don’t use, are organic too. This is because synthetic fertilizers are made of molecules that are made of mostly carbon atoms.

In fact, most chemists laugh a little when they see the word organic on food packages in the grocery store. All food is made of carbon-based molecules, and so are most food additives, whether they’re natural or synthetic. So to a chemist, all food is “organic.”

How in the world did this happen? Why do chemists use the word organic so differently from everyone else? Living things are sometimes called organisms. A long time ago the word organic was used to describe anything that came from an organism—anything that came from a living thing. Chemists who worked with substances found in living things were called organic chemists.

Just about every substance you pull out of a plant or animal is made of mostly carbon atoms—except water, of course. In time, organic chemists learned how to turn plant and animal compounds into all kinds of other things. Chemists used plant and animal compounds to make new compounds that are not found in nature. Even though these substances weren’t natural, they had something in common with plant and animal matter: their molecules were still made of carbon atoms. After all, when chemists turn one substance into another, all they are doing is taking apart its molecules and putting the atoms back together in different ways. Carbon in, carbon out.

Organic chemists also figured out how to synthesize a lot of natural plant and animal compounds from nonliving materials. In 1827 a chemist named Friedrich Wöhler was playing with some mineral salts. He accidentally made urea, a compound found in urine. He wrote to a friend saying, “I can no longer, so to speak, hold my chemical water and must tell you that I can make urea without needing a kidney, whether of man or dog.”

There was more to come. Petroleum is mostly carbon. Scientists learned how to make all kinds of other plant and animal compounds from it. For example, they made vitamins and sugars from petroleum. Organic chemists branched out even further. They started making new carbon-based materials from nonliving things. They made everything from gasoline to plastics out of petroleum. With all this branching out, organic chemistry grew to be the chemistry of all carbon compounds, whether or not they came from living things. Petroleum, gasoline, and plastics are all carbon-based, and so they came to be considered organic by chemists.

So here we are today, with the word organic meaning “carbon-based” to chemists and meaning “natural” to everyone else. There’s a real reason for chemists to have their own meaning for the word organic, and it has to do with a concern in chemistry for how substances behave. A substance behaves or reacts the way it does because of the atoms its molecules are made of, and how they are put together. This means carbon-based compounds should behave differently from compounds based on other elements. Therefore, it is useful for chemists to group carbon-based compounds together because they are similar in a chemically interesting way.

But from the perspective of the way compounds react or behave, there is no such reason for chemists to separate natural compounds from synthetic compounds. If two molecules are made of the exact same atoms put together in the exact same way, they are going to behave in the exact same way, even if one molecule was made in nature and the other was made by a scientist in a laboratory. Moreover, there aren’t really any properties that all natural materials have that synthetic materials don’t have, and vice versa. Both natural and synthetic substances can be deadly; and both natural and synthetic materials can be safe to eat.

So when we talk about “organic chemists,” we’re not talking about chemists who only use all-natural substances. We’re talking about chemists who make and study compounds that are made of carbon, whether the compounds are natural or synthetic.

Return to the Main Story

Return to the Main Story
Meanwhile, In the Rest of the World...