Chemical reactions occur when elements or compounds combine and create new compounds. Elements are substances that contain only one type of atom and are represented by unique symbols on the periodic ...

an element contains just one type of atom a compound contains two or more types of atom joined together a mixture contains two or more different substances that are not joined together the different ...

What is an atom? Well, everything is made of atoms! Atoms themselves are made of smaller particles. In this National 4 Chemistry study guide, learn about how elements can join together in different ...