Question
SNC1W1 - Chapter 5.2/5.3
Part B: Decide whether a physical or chemical change has occurred and give
1.
2.
Scenario
Physical or
Chemical
Change?
Umm! A student removes a loaf of bread hot from the
oven. The student cuts a slice off the loaf and spreads
butter on it.
Physical
No chang
No unex
change or
Your friend decides to toast a piece of bread, but leaves
it in the toaster too long. The bread is black and the
kitchen if full of smoke.
You forgot to dry the bread knife when you washed it
and reddish brown spots appeared on it.
3.
4. You blow dry your wet hair.
5.
In baking biscuits and other quick breads, the baking
powder reacts to release carbon dioxide bubbles. The
carbon dioxide bubbles cause the dough to rise.
You take out your best silver spoons and notice that
they are very dull and have some black spots.
6.
7. A straight piece of wire is coiled to form a spring.
8. Food color is dropped into water to give it color.
9.
Chewing food to break it down into smaller particles
represents a
change, but the changing of
starch into sugars by enzymes in the digestive system
represents a
change.
10. In a fireworks show, the fireworks explode giving off heat
and light.
Part C: True or False?
Answer
1. Physical Change; 2. Chemical Change; 3. Physical Change; 4. Physical Change; 5. Chemical Change; 6. Chemical Change; 7. Physical Change; 8. Physical Change; 9. Chemical Change; 10. Physical Change.