1. The document discusses factors that contribute to chemical changes in materials, such as the presence or lack of oxygen and application of heat. 2. It states that the presence of oxygen and application of heat or changes in temperature are needed for chemical changes to occur in materials like paper, wood, and fuels during combustion. 3. The document also explains that chemical changes transform the materials and the products cannot revert to their original forms. Burning is impossible without sufficient heat, fuel, and oxygen.

2. Investigate changes that happen in
materials under the following
conditions
• presence or lack of oxygen
• application of heat.
(S5MT-Ic-d-2)

3. FACTORS
THAT
CONTRIBUT
E TO
CHEMICAL
CHANGE

4. THESE ARE THE :
1. application of heat
or change in
temperature
2. presence of
oxygen

6. Cooperate with your
group
Observe silence
Maintain cleanliness
Listen to the reporter

8. Certain conditions are needed
for chemical change to happen.
These are the application of
or with a change in
and presence of oxygen. Paper,
wood, candle or any fuel can
decompose into ash. In the
process of combustion heat, fuel
and oxygen are needed to

9. Burning is impossible if any of
the factors is missing. The
process of combustion changes
the materials chemically. The
product of this cannot be
returned to its original form.
Some chemical in materials may
transformed into heat or light
and the remains in the process is

10. Read each question carefully. Write the letter of the
correct answer in your notebook.
1. Which of the
following
gasses is
needed in
combustion
process?
A.Carbon
B. Oxygen
C.Helium

11. Read each question carefully. Write the letter of the
correct answer in your notebook.
2. Which pair is
needed to for
chemical
change to
happen?
A. Heat and fuel
B. Heat and
carbon
C. Heat and
oxygen

12. Read each question carefully. Write the letter of the
correct answer in your notebook.
3. The remain
product in
the process
of burning
is______.
A.Water
B.Smoke
C.Ash

13. Answer the question briefly.
4-5. Is it easy to
control a
grassfire on
summer, when
there is a
presence of
blowing wind?
Why?

14. Bring the following
tomorrow
2 pieces apple
2 pieces potato
Cutter or knife
Rubber bands
Plastic plate

15. CHANGES
IN MATTER
DUE TO THE
PRESENCE
OF
OXYGEN

16. Do you know why fruits
ripe and eventually rot?

17. Cooperate with your
group
Observe silence
Maintain cleanliness
Listen to the reporter

18. 1. Slice the two apples.
Tie the other apple with
rubber bands.

19. Do the same with the
potatoes and bananas..

20. P.15
FRESHLY CUT APPLE

23. GLASS A GLASS B (W/ VITAMIN C)

24. FRESHLY CUT AFTER 5 HOURS
GLASS A GLASS B

25. Guide Questions:
1. What happened to the
exposed parts of the
apple? potato? banana?
2. What causes the change
in color of exposed parts
of the potato? Apple?
Banana?

26. CHANGES
IN MATTER
DUE TO THE
PRESENCE
OF
OXYGEN

27. Remember , the presence or absence of oxygen
cause changes in the materials. Vitamin C acted
as antioxidant that prevents the apple to turn
brown in color. This way, the apple will keep its
good appearance. Now, you understand why
apple and eggplants turn brown or showed
discoloration when exposed to oxygen.

29. What made the exposed
part of the fruit darkened
in color?

30. How does OXYGEN affects
chemical change in some
materials?
1. Presence of oxygen can
decompose fruits and spoil
food.

31. 2. Exposure of some sliced fruits
and vegetables to oxygen cause
then to turn brown or dark.

32. 3. It can cause rust on metals.

33. Vacuum packing it removes air from the package
prior to sealing. The intent of vacuum packing is
usually to remove oxygen from the container to
extend the shelf life of foods and, with flexible
package forms, to reduce the volume of the
contents and package

34. Since rust makes materials
break easily, these structures
are coated with paint to keep
oxygen from reacting directly
with it.

35. When fleshy fruits such as apples, pears,
peaches, and bananas are cut open and
exposed to the air, their insides will often
turn brown within minutes as a result of the
oxidation process. Although brown fruit is
still nutritious and safe to eat, sometimes
the color can appear unsightly and
unappetizing. However, there are several
natural ingredients you can use together to
prevent your fruit from turning brown.

36. How to keep fruits from turning
brown when sliced.
1. Using honey and water
30 seconds

37. How to keep fruits from turning
brown when sliced.
2. Using lemon juice and water.
5 mins

38. How to keep fruits from turning
brown when sliced.
3. Using salt and water
6 mins

39. CHANGES
IN MATTER
DUE TO THE
LACK
OF
OXYGEN

40. Describe the changes
happen to the following due
to presence of oxygen:
Iron
Fruits
Food

41. Describe the changes that
happened in each picture.

42. Describe the changes
happened in each picture.
What changes will take place
when you chop a wood?
What changes will take place
when you burn the wood?
What will happen to the
burning process of the wood
if there is no oxygen?

43. EFFECTS
OF LACK
OF
OXYGEN

44. 1. Living things are dependent
to oxygen for breathing.
Lack of oxygen to the brain
may result to nausea and
vomiting.
2. Without oxygen, Nature
cannot produce CO2, in this
case plants cannot make
their own food.

45. 3. Combustion is impossible
in the absence of oxygen
and in this condition we
cannot cook our food.