I.OBJECTIVES:Through experiments, the pupils with 75% accuracy are expected to
a. define physical and chemical change
b. distinguish the difference between physical and chemical change
c. perform the activity given
II. SUBJECT MATTER:
Topic: Physical and Chemical Change
References: Exploring and Protecting our World by Carmelita Coronel, pp.134-145
Science for Daily use by Conchinta Tan, pp.126-130
Science for everyone by Ruth G. de Lara, pp.162-167
III. MATERIALS:
Chart, Petri dish,. Wire gauze, alcohol lamp, match, cube of ice,
Iron filings, sulfur, magnet, clear sheet of paper, metal bottle cover, tongs, burner
IV. PROCEDURE:
A. Motivation & Statement of the problem
Everything in our environment is changing. Do you agree, class? (yes)
So, can you cite some changes taking place in our environment? (changes in weather, changes of the color of the leaves.)
How about in yourself? Now you’re already a grade 5 pupil, I want you to recall those years when you were just a grade 1 pupil. Have you noticed some changes? (yes)
So, what are those changes? (changed in height, size, and weight)
Aside from those changes in yourself, what else in those world change? (things)
So, can you cite some examples showing that things change (glass that was broken, a wood that was burned, a piece of paper that was cut)
Do you know class that there are 2 kinds of changes in a thing? (no)
And then what would you want to know now? (What are the 2 kinds of changes?)
So now we will have an activity for you to find out the 2 kinds of changes.
B. PRESENTATION
The teacher groups the class into two. The first group is assign to perform Activity I and the second group is assign to perform Activity II.
The teacher presents the materials needed and the procedure in each activity.
ACTIVITY I
MATERIALS:
Petri dish alcohol lamp wire gauze match cube of ice
PROCEDURE:
1. Put a cube of ice on a Petri dish.
2. Place it at room temperature for 5 minutes.
3. Observe what happens.
4. Once it turns liquid, heat it up.
5. If you can, hold the cover of Petri dish and catch some stream.
6. Observe what happens to the water while it is being heated.
7. Observe what is formed on the cover.
ACTIVITY II
MATERIALS:
Iron filings tongs burner sulfur match magnet
metal bottle cover
clear sheet of paper
PROCEDURE:
1. On a clean sheet of paper, make a mixture of iron filings and sulfur.
2. Mix them well, and put the mixture in a bottle cover.
3. Using a pair of tongs, hold the bottle cover over a burner.
4. Heat up the mixture.
5. Observe what happens.
6. Try passing a magnet over the substance.
7. Observe the iron filings in relation to the magnet.
C. WORK PERIOD
The teacher asks the group 1 to perform the first activity given and asks the rest of the class to observe. After the group 1 performs, the teacher then asks the group 2 to perform the second activity assigned to them and asks the rest of the class to observe. The teacher facilitates and observes each group especially in handling the materials.
D. DISCUSSION OF RESULTS
The teacher asks the pupils:
In the first activity what have you observed when the ice cube was placed at room temperature for 5 minutes? Was there any changes happen? (yes) (the ice cube was melted)
While the water was being heated, what have you observed? (the water was boiling.)
How about the cover, what have you observed? (a moist was formed)
Now, let’s take a look at your group 2’s activity.
What have you observed when the iron filings and sulfur was being heated? (the sulfur was melted.)
Class, before we perform the second activity, we observed that iron filings sticked to the magnet but when the mixture was being heated, do the iron filings still stick to the magnet ? (no, it didn’t filings become a nonmagnetic substance .)
E. CONCLUSION
So now, can you cite the differences between the changes in activity I and activity II ?
(In activity I, there is no changes in composition, even ice cube turns to liquid it still water and even it is being heated it is still water, while in activity II the composition changed, a new substance was formed iron filings became nonmagnetic substance.)
So now, do you know the two changes? (yes, physical and chemical change.)
If the pupils cannot answer, the teacher allows the pupil to open their books on page 137-140. The pupils can already answer: physical change and chemical change.
F. APPLICATION
A. Put a check mark ( ) in the appropriate number if the situation shows a physical change and wrong ( ) if it shows chemical change.
__________1. sharpening a pencil
__________2. ripening of mango
__________3. cutting of fingernails
__________4. burning of a candle
__________5. folding of a piece of paper
__________6. freezing of ice
__________7. souring of a piece of cake
__________8. digesting food in the stomach
__________9. ironing of clothes
__________10. sweetening of a sour fruit
__________11. burning of wood
__________12. cutting a cake into halves
__________13. grinding of meat
__________14. drying of clothes
__________15. grilling of meat
__________16. boiling of water
__________17. souring of milk
__________18. breaking of a glass
__________19. heating of neal
__________20. chopping meat into pieces
V. EVALUATION
A. Describe the changes that take place in each of the following conditions.
CONDITION
1. pounding of grains of salt
2. pruning of leaves
3. piling of books
4. burning of twigs
5. heating of water
B. Choose the letter of the best answer.
1. In which condition will rusting occur easily?
a. near the seashore b. away from the seashore c. both a and b
2. when iron rusts, it produces a material that is_______
a. hard b. strong c. weak
3. Which is true about chemical change?
a. a new material is formed
b. the product can be changed to its original form
c. both a and b
4. Which is the following is the product combining iron and oxygen?
a. rust b. galvanized iron c. both a and b
5. Which of the following is an example of chemical change?
a. magnetizing iron filings
b. cutting a piece of wood
c. rusting of a steel wool
VI. ASSIGNMENT
List down 5 importance of physical change and 5 importance of chemical change.
