Answer;
-A compound
Step-by-step explanation;
-Any substance that contains only one kind of an atom is known as an element. Because atoms cannot be created or destroyed in a chemical reaction, elements cannot be broken down into simpler substances by chemical means. Elements are made up of atoms, the smallest particle that has any of the properties of the element.
-Elements combine to form chemical compounds that are often divided into two categories. A compound contains atoms of different elements chemically combined together in a fixed ratio. They contain only one type of molecule. Elements that compose the compound are chemically combined. A compound can be separated into simpler substances by chemical methods/reactions.