It seems like every other day we hear about some hacker, tinkerer, maker, coder or one of the many other Do-It-Yourself engineer types getting ... to convert basic chemical formulas, such as ...

A pure substance made from more than one type of element chemically bonded together. Elements bond in fixed ratios and so can be represented by a chemical formula. For example, sodium chloride has ...

For example, magnesium oxide is made up of two elements, magnesium and oxygen. Its formula is MgO. This shows that it has one atom of magnesium for every one atom of oxygen.