Identifying physical and chemical changes

1. Topic One Identifying physical and chemical changes

2. Physical Change- • A change to a physical property of the substance • Shape, state of matter, color, dissolving (nothing disappears)

3. Chemical change- • A change in the chemical make up of a substance, a new substance is formed • Bubbling, burning, oxidizing, rotting, souring, odor change, unpredictable color change

4. Phenol red and carbon dioxide Phenol red goes from pink to yellow when exposed to carbon dioxide This is a chemical change The indicator (color) is chemically changed by the substance it is put into.

5. Water and green food coloring The clear water turns green when the food coloring is added This is a physical change The water has not been chemically changed (it’s still water) and the green food coloring can be removed!

6. Burning candle The wax melts and the wick burns, you cannot get the burned part of the candle back This is a physical & chemical change The wax melts and then evaporated because of the heat of the flame The wick is burned and turned into a new substance

7. Ice in a beaker The ice placed into the beaker melts This is a physical change The heat from the room is transferred to the ice cube, warming it up and causes the solid water to turn into liquid water