Evidence of chemical reactions include -



light production, color change (new/different), gas production (bubbles/fizzing - not boiling), precipitate, and temperature change



no light production, color change (new/different), gas production (bubbles/fizzing - not boiling), precipitate, and temperature stays the same



color change (new/different), gas production (like when a soda is opened), precipitate, and temperature stays the same



light production, color change (like adding food coloring to water), gas production (like when a soda is opened), precipitate, and temperature change