Presentation on theme: "Physical Change & Chemical Change. Physical Change A change that affects 1 or more physical properties. Examples – a melting popsicle, cutting wood, dissolving."— Presentation transcript:
Physical Change & Chemical Change
Physical Change A change that affects 1 or more physical properties. Examples – a melting popsicle, cutting wood, dissolving sugar, crushing a can DOES NOT AFFECT THE IDENTITY of the matter.
Chemical Change Occurs when 1 or more substances change into new substances that have new or different properties. Examples – milk goes bad, Efferdent tablets reacting in water, fireworks going off, baking a cake.
Chemical Change Signs of a chemical change – change in odor, change in color, release of energy (sound, heat, light), bubbling, precipitate forming Precipitate – a solid formed when 2 substances dissolved in water form
Chemical Change Chemical properties describe whether a chemical change will occur or will not occur chemical change = chemical reaction
Chemical Change vs. Physical Change Chemical change – Changes composition of a substance, or what its made of. Changes its identity Physical change – Does not change the composition of a substance, only its appearance. Does not change its identity.
Reversing a change Physical change – use physical properties. Usually pretty easy. Chemical change – use chemical properties. Not as easy to do, or sometimes impossible.