1. PHYSICAL AND CHEMICAL
CHANGES

2. PHYSICAL AND CHEMICAL CHANGES
Matter can change both physically and chemically.
Law of conservation of matter: whatever kind of change happens to matter– the total amount of matter present will remain the same.

3. PHYSICAL CHANGES OF
MATTER

4. PHYSICAL CHANGE
Any change in state, shape, size, in which the identity of the substance does not change.
A ball of clay even after changing its shape will still be clay.
An ice cube melting from solid to liquid.

5. PHYSICAL CHANGE Solubility: The process by which a solid,
liquid, or gas forms a solution
in a solvent.
Solvent is what another
substance is dissolved in.
Solute is the substance
being dissolved.

6. PHYSICAL CHANGE Changing States of matter:
the identity of the substance does not change.

7. PHYSICAL CHANGE Melting: When solid changes to liquid.
When ice melts it changes its state to water.

8. PHYSICAL CHANGE Freezing: Occurs upon cooling. A substance changes its
state from liquid to solid.
Freezing temperature
varies from one
substance to another.

9. PHYSICAL CHANGE
Vaporization is the change of matter from liquid to gaseous state. There are two types:
1- Evaporation:
Occurs on the surface
of the liquid only.
Is an essential part of
the water cycle.
Water, even at room
temperature,
evaporates without
anyone noticing it.

10. PHYSICAL CHANGE Vaporization: Another type is-- 2- Boiling:
Occurs on the entire mass
of the liquid.
Boiling point of various
substances varies from one
substance to another.
Example: water boils at
100 ° C.

11. PHYSICAL CHANGE Condensation: Is the opposite of evaporation.
Change from gaseous to liquid form.
Occurs when vapor is cooled
Morning dew is an example of condensation.

12. PHYSICAL CHANGE Sublimation:
Change of state directly from solid to gaseous form.
Iodine sublimates upon heating.

13. PHYSICAL CHANGE Deposition: Settling of particles from a solution.
Opposite of dissolution.

14. EXAMPLES OF
PHYSICAL CHANGES

15. TEARING OF A PIECE OF PAPER

16. MELTING CHOCOLATE

17. CRACKING AN EGG

18. CHOPPING A PIECE OF WOOD

19. MIXING A CAKE BATTER

20. MELTING CANDLE WAX

21. MIXING WATER AND ACID

22. MAKING A SOLUTION OF SALT AND WATER

23. THE REASON FOR CHEMICAL CHANGES
CHEMICAL REACTION
THE REASON FOR CHEMICAL CHANGES

24. CHEMICAL REACTION
A Chemical Change is a process in which substances undergo chemical reaction. A completely new substance forms and it is irreversible.

25. SIGNS OF
CHEMICAL CHANGE

26. CHEMICAL CHANGE
Production of Gas: bubbles are formed within a liquid during a chemical reaction if gas is released.
Example: When vinegar is added to baking soda bubbles are formed showing that carbon dioxide is released. =

27. CHEMICAL CHANGE Formation of Precipitate: A precipitate is a solid
formed during a chemical
reaction in a solution.
New substance is insoluble
and settles at the bottom.
Example: Silver Nitrate &
Sodium chloride solutions react
together, precipitate of silver
chloride settles at the bottom of
The clear solution.

28. CHEMICAL CHANGE Color change: The new substance formed may reflect
different colors of
light.

29. CHEMICAL CHANGE Change in temperature:
Either heat is released (exothermic reaction) and the container may feel hotter OR
Heat is absorbed (endothermic reaction) and the container may feel colder.

30. CHEMICAL CHANGE Emission of Light:
Light is give out as result of a chemical reaction.
Example: light stick, neon lights

31. CHEMICAL CHANGE Smell change: Change in odor during a chemical
reaction.
For example:
Change in smell
when milk goes
bad.

32. EXAMPLES OF
CHEMICAL CHANGES

33. BURNING OF A PAPER

34. BURNING OF A CANDLE

35. BAKING A CAKE

36. ADDING BAKING SODA TO VINEGAR

37. BURNING OF WOOD IN THE FIREPLACE

38. LIGHTING A MATCH STICK

39. LET’S CHECK OUR UNDERSTANDING
OF PHYSICAL &
CHEMICAL CHANGES