Final answer:
Elements are pure substances, compounds are made up of two or more elements chemically combined, and mixtures are physically combined substances that can be separated
Step-by-step explanation:
Elements
Elements are pure substances that cannot be broken down into simpler substances by chemical means. Each element is made up of only one type of atom. Examples of elements include hydrogen, oxygen, and carbon.
Compounds
Compounds are substances made up of two or more elements chemically combined in a fixed ratio. Compounds have different properties from the elements they are made of. An example of a compound is water, which is made up of hydrogen and oxygen.
Mixtures
Mixtures are made up of two or more substances that are physically combined and can be separated by physical means. The components of a mixture retain their individual properties. Examples of mixtures include saltwater and air.
Learn more about Differences between elements, compounds, and mixtures