Classify each of the following pure substances as an element or a compound: b. hydrogen peroxide (H₂O₂)

Elements are pure substances that consist of only one type of atom and cannot be broken down into simpler substances by chemical means. Each element is represented by a unique symbol on the periodic table, and they are the fundamental building blocks of matter. Examples include hydrogen (H), oxygen (O), and carbon (C).

Compounds are substances formed when two or more different elements chemically bond together in fixed proportions. They have distinct properties that are different from the individual elements that compose them. For example, water (H₂O) is a compound made of hydrogen and oxygen, while hydrogen peroxide (H₂O₂) is another compound that contains the same elements in different ratios.

A chemical formula is a symbolic representation of a compound that indicates the types and numbers of atoms present. For instance, the formula H₂O₂ for hydrogen peroxide shows that it contains two hydrogen atoms and two oxygen atoms. Understanding chemical formulas is essential for classifying substances as elements or compounds and for predicting their chemical behavior.