There are several ways to distinguish between metals and non-metals, but two key methods are:
- Physical Properties: Metals tend to have a shiny, lustrous appearance and are typically solid at room temperature (with the exception of mercury). They are good conductors of heat and electricity and are malleable, meaning they can be shaped or hammered without breaking. Non-metals, on the other hand, often have a dull appearance and can be found in various states at room temperature (gases like oxygen, solids like sulfur). Non-metals are generally poor conductors of heat and electricity.
- Chemical Behavior: Metals usually lose electrons during chemical reactions, forming positive ions (cations), whereas non-metals tend to gain electrons, forming negative ions (anions). For example, when sodium (a metal) reacts with chlorine (a non-metal), sodium donates an electron to chlorine, resulting in the formation of Na+ and Cl–. This difference in electron behavior can be tested through simple reactions, such as observing how substances react with acids or bases.
By examining an element’s physical properties and chemical behavior, you can usually determine whether it is classified as a metal or a non-metal.