Metals are generally identified by their properties. Most of the metals have a luster (shiny appearance). Most of the metals are good conductors of electricity. So if some unknown solid conducts electricity, there is high likelihood that it is a metal. Metals are generally malleable and ductile. So, if a unknown solid can be bent without breaking, it is most likely a metal. Metals are also non-gaseous, so if an unknown sample is gas at room temperature, then it is not a metal. If we need to identify a metal in a chemical substance, it is probably the electron donor or cation (the ion that has a positive charge due to loss of electron/s). Metals can be more accurately identified by more detailed laboratory analysis.
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