What are 3 signs that a chemical change (chemical reaction) has taken or is taking place?

Heat has been released or lost. Odor may be present. Absence of a substance may be converted to something else.

Non metal is an element or substance that is not a metal metal is a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivitymetalloid is an element (e.g., germanium or silicon) whose properties are intermediate between those of metals and solid nonmetals. they are electrical semiconductors.