Answer : Explanation : An atom is the smallest particle of a substance. Chemical substances are divided into two major groups. They are1. Pure Substances (and)2. Mixtures. There are two types of pure substances that are Elements and Compounds. Elements : An element is a substance that is made up of only one kind of atoms and cannot be broken down into simpler substances by chemical means. Metals and Non- metals come under elements.Examples of elements are Iron, Silver, Gold, Mercury etc. Compounds : A Compound is a substance that is formed when two or more elements combine chemically.Examples of compounds are Water, Carbon dioxide, methane, vinegar etc. Mixtures : A Mixture is formed when two or more substances mixed together but not chemically combined.Example: Air.
Click here to see the full blog post