A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. The ratio of each element is ...

There are lots of different substances but only just over a hundred elements. An element is a substance that is made up of only one kind of atom. The atoms in a particular element are the same as each ...

Chemical Reactions: A chemical reaction is a process where the substances 8unbdergo a change in their chemical composition. The substances that enter the reaction are called reactants that are then ...