A compound that only contains one type or class of atom is said to become an element. As it cannot be altered through physical or chemical suggests to stop working or produce new substances, an element is often a pure substance. The majority of elements are metals, nonmetals, or metalloids. https://jeffreyektcp.tkzblog.com/35998497/considerations-to-know-about-các-trường-nội-trú-nhất-đi-a-ba-n-tphcm