What Is a Chemical?

Short answer: Everything is a chemical. Longer answer: Chemistry is the study of matter and its interactions with other matter. Anything made of matter is therefore a chemical. Any liquid, solid, gas. Any pure substance; any mixture. Water is a chemical. Technically speaking, so is a chunk of your computer. A chemical can often be broken down into components, as is true with your computer. However, people generally use the term 'chemical' to refer to a substance that appears homogeneous or the same throughout its structure.