The basic building block of matter is the atom, the smallest unit of an element that can enter into combinations with atoms of the same or other elements. Chemists use the scientific method to perform experiments, pose hypotheses, and formulate laws and develop theories, so that they can better understand the behavior of the natural world.

In many substances, atoms are combined into molecules. Chemistry deals with the composition, structure, and properties of matter, and the ways by which various forms of matter may be interconverted.

element — substance that is composed of a single type of atom; a substance that cannot be decomposed by a chemical change. law — statement that summarizes a vast number of experimental observations, and describes or predicts some aspect of the natural world. scientific method — path of discovery that leads from question and observation to law or hypothesis to theory, combined with experimental verification of the hypothesis and any necessary…. symbolic domain — specialized language used to represent components of the macroscopic and microscopic domains, such as chemical symbols, chemical formulas, chemical equations, graphs, drawings….