Chemistry is the scientific study of matter and its properties, as well as the changes it undergoes. The term 'chemistry' can refer to a variety of topics, including the study of elements and compounds, their structure and composition, and the ways in which they interact with each other. Two of the most important concepts in chemistry are ATTRACTION and ATOM. ATTRACTION is the force that binds atoms together to form molecules, while an ATOM is the smallest unit of matter that retains its chemical properties.