1. Physical and Chemical Change

2. Clues of a Chemical Change
A new colour appears
eg. Oxygen Indicator Solution

3. Clues of a Chemical Change
A solid material (called a precipitate) forms in liquid
Heat or light is given off

4. Clues of a Chemical Change
Bubbles of gas are formed
The change is difficult to reverse

5. Situation  Explanation
A piece of dry ice (solid carbon dioxide) is dropped into hot water. Large amounts of white vapour bubble out of the water. 
Physical
Chemical
Explanation
The bubbles are carbon dioxide gas. There was no chemical change. Just a change in state.

6. Situation  Explanation
When George’s father makes wine from crabapples, bubbles form on the surface of the yeast and fruit mixture.
Physical
Chemical 
Explanation
A chemical change from apple juice to wine, it is no longer the same compound.

7. Situation  Explanation
When margarine is left in a warm place for an extended period of time, it tastes sour.
Physical
Chemical 
Explanation
The margarine is rotting, which is why it tastes sour.

8. Situation  Explanation
Jane’s father opens up a new deodorant product. The room quickly smells like fresh flowers. 
Physical
Chemical
Explanation
The deodorant is still deodorant, some particles have changed to vapour which we smell.

9. Situation  Explanation
During a school volleyball game, Jennifer sprains her ankle. Her coach squeezes a bag at room temperature that quickly becomes very cold.
Physical
Chemical 
Explanation
Inside the bag a chemical change has occurred which is endothermic.