Carbon (C), from the Latin word for coal, carbo, is an essential element that is found in more molecules than any other element. Carbon is a tetravalent element, which allows it to combine directly with up to 4 other elements. Despite this, carbon is rather inert under standard conditions. It also has no melting point, instead having what is known as a triple point – a temperature and pressure at which it exists as a solid, liquid, and gas. At standard pressure, carbon sublimates from a solid into a gas. Carbon is electrically conductive, as well as being the most thermally conductive element.

You are undoubtedly familiar with two of carbon’s allotropes (molecules formed of one element, ex. O₂ is oxygen gas, O₃ is ozone), graphite and diamond. However, carbon also forms a third allotrope called Buckminster fullerene, which is C ₆₀. Graphite was once known as false lead in Latin, hence it being referred to as pencil lead. Pencil lead also contains clays, so it is not pure graphite. However, pure graphite is used in heavy duty batteries. A 6 volt “heavy duty” lantern battery (non-alkaline) is an ideal candidate. Usually the lanterns come with one; Energizer and Duracell are alkaline and will not work.

A 6 volt lantern battery. Energizer and Duracell use alkaline cells, which do not contain carbon rods.

Instructions for disassembling lantern batteries to get the graphite rod can be found on the internet. The battery I took apart came with handy connectors to use the rods as electrodes. The carbon rods were also secured into the electrolyte, which required a bit of effort to disconnect. I got tired of dealing with the very sticky electrolyte coating, and tossed the uncapped cell into my outdoor fireplace, which burned everything but the graphite rod. I soaked it in Coca Cola to strip away any remaining impurities.

I later took another stab, as I needed the Manganese (IV) dioxide. I sliced the top plastic cap, and then used a flathead screwdriver to pry it off. A paper membrane was under that, coated in a sticky purple gel. Below that was the powdered manganese dioxide, which I gradually dug out with the screwdriver until I could wiggle the rod free. Again, I rinsed it and soaked it in Coca cola. The outer metal casing is also pure zinc.

You could also use a diamond to represent this element, but most people don’t have extra diamond laying around.