Carbon: the multi-tool of elements
From thick and grimy oil to gleaming diamonds, carbon can take on many roles
How this basic element is the building block of life and everything
With a pencil, we can draw a picture of how useful the element carbon is. A pencil’s lead is not the poisonous metal of the same name. Instead it’s pure carbon, in a form known as graphite. In graphite, sheets of carbon atoms stack up in layers. When we write in pencil, we’re leaving behind carbon sheet after carbon sheet. On their own these sheets are called graphene, which is very strong and special in many other ways.
The wood around the graphite lead also contains many carbon atoms connected with atoms of other elements, most importantly hydrogen. Our fingers are made of the same types of atoms as wood, but are soft and spongy, unlike the hard pencil materials. Combined with other atoms like this, carbon is found in all living things. It’s also in fossils of things that lived long ago, both as carbonate rocks like chalk and as fossil fuels like natural gas, crude oil and coal.
And when crushed inside the Earth, carbon forms beautiful diamond gems. All these different forms make carbon very important. Humans use it to make many things, including plastic. We can turn rocks into sturdy iron metal and even stronger steel metal alloys, also with carbon.
Fuel carbon burns, moving vehicles and generating electricity. When burning, carbon atoms combine with oxygen atoms from the air, making the greenhouse gas carbon dioxide. In small amounts this keeps Earth warm enough for us to live here. But humans now burn too much, making the world too hot as a result.
However, plants suck carbon into their leaves and stems from carbon dioxide in air. So having enough trees to pull carbon from the air is very important. Even cutting some trees down to put carbon in your pencil is better than burning wood and warming everything up.