Science 7 - Changes in Matter(Physical and Chemical).ppt

Physical and Chemical Changes in Matter

2. To study the difference
between a physical and
chemical change.

3. Matter is everywhere.
Matter is anything that takes up space
and has mass.
Matter is constantly experiencing both
chemical and physical changes.

4. A physical change alters the form of a
substance, but does not change it to another
substance.
It changes shape or size
It dissolves.
It changes phase (freezes,
boils, evaporates, condenses)
Example:
Making Orange Juice

5. Physical changes occur when matter changes its
property but not its chemical nature.
Physical property changes could include a change
in: texture, shape, size, color, odor, volume, mass,
weight, and density.

6. Crushing an aspirin
A Boiled egg
Physical
C
hange

7. Cutting paper?
Physical Change

8. Physical Change
Ice melting?

9. Physical Change
Sawing
wood?

10. Disappearing
puddle?
Physical Change

11. Dry ice?
Physical Change

12. Chemical changes are changes matter undergoes
when it becomes new or different matter.
It burns
Temperature changes without heating/cooling
It bubbles (makes a gas)
It changes color
It forms a precipitate

13. When a substance undergoes a chemical change, it is changed
into a different substance with different properties.
To identify a chemical change look for signs such as color
change, bubbling and fizzing, light production, smoke, and
presence of heat.
Example:
Baking a Cake

14. 1.Precipitation
2. Color Change

15. 4. Temperature
Change
3. Gas Production

16. A chemical change occurs when fireworks are
used. Fireworks are made of metals such as
magnesium and copper. These change chemically
as they light up the sky.

17. Lighter fluid burining
C
hem
ical
C
hange

18. Sugar dissolving in tea
Examples for Chemical Change
Logs burning
Breaking water
up by separating
it into hydrogen
and oxygen

19. Toast burning?
Chemical Change

20. Rocket fuel burning?
Chemical
Change

21. Metal rusting?
Chemical Change

22. Candle burning?
Chemical Change

23. Tears up paper?
Physical change
Mixes salt and water?
Physical change
Burns paper?
Chemical change
Evaporates salt water?
Physical change
Mixes vinegar and baking soda?
Chemical change

24. Classify the following changes as physical
change or chemical change.
Chopping wood frying meat
Grinding meat browning of apple
Burning wood baking a cake
Melting ice folding a piece of paper
Blending of apple boiling water
Breaking a glass frying an egg
Iron rusting rotten banana
Milk going sour