Chemicals are substances made up of atoms and molecules that have specific properties and structures. They can be found in everything around us, from the air we breathe to the food we eat. For example, water is a chemical made of two hydrogen atoms and one oxygen atom. Chemicals can be natural, like those found in plants, or synthetic, created by scientists in laboratories. In everyday life, chemicals play important roles. Cleaning products contain chemicals that help remove dirt and germs, while medications are made of chemicals that can help us feel better when we're sick. Understanding chemicals helps us appreciate how they affect our health and the environment.