Lesson 2 Changes in Matter
Worktext Pages: 28–43
Suggested Number of Meetings: 3 |
Lesson Objectives
At the end of the lesson, the pupils are expected to
1. differentiate physical and chemical changes; 2. classify changes in matter as physical or chemical; 3. demonstrate and explain how heat can cause change in matter; and 4. demonstrate and explain how the presence or lack of oxygen can cause change in matter. |
Corresponding K to 12 Curriculum Learning Competencies
The learners should be able to investigate changes that happen in materials under the following conditions:
• presence/lack of oxygen and • application of heat. |
ESSENTIAL QUESTIONS
• How can matter change physically or chemically?
• How does the change in temperature cause a change in matter?
• How does the presence or lack of oxygen cause a change in matter?
• How does the change in temperature cause a change in matter?
• How does the presence or lack of oxygen cause a change in matter?
TECHNOLOGY AND RESOURCES
• Real-Life Science 5 worktext, pages 28–43
MATERIALS
• materials for ice cream making:
½ teaspoon vanilla ½ cup rock salt
1 cup all-purpose cream 2 quart-size zip-top bags
2 tablespoons sugar 1 gallon-size zip-top bag
4 cups crushed ice
• materials for egg sandwich making:
raw egg fork
salt stove
bread pan
mayonnaise cooking oil
bowl
• computer
• LCD projector
½ teaspoon vanilla ½ cup rock salt
1 cup all-purpose cream 2 quart-size zip-top bags
2 tablespoons sugar 1 gallon-size zip-top bag
4 cups crushed ice
• materials for egg sandwich making:
raw egg fork
salt stove
bread pan
mayonnaise cooking oil
bowl
• computer
• LCD projector
LEARNING PLAN
Introduction
1. Ask the pupils to look at the pictures on page 28 of the worktext. Let them examine each picture and tell the changes that took place in the materials shown. Introduce the word change.
2. Give the pupils an overview of what they will learn in the lesson. Show them the essential questions that they should be able to answer and the tasks that they should accomplish as they tackle the lesson.
2. Give the pupils an overview of what they will learn in the lesson. Show them the essential questions that they should be able to answer and the tasks that they should accomplish as they tackle the lesson.
Learning Experiences/Lesson Development
Physical Change
1. To motivate the pupils, engage them in an ice cream making activity. Demonstrate and then instruct them to do the following procedures:
a. Pour the all-purpose cream, vanilla, and sugar into a quart-size zip-top bag. Taste the mixture.
b. Squeeze out air and seal the bag tightly. Shake it lightly to mix the ingredients.
c. Place the tightly sealed bag inside another quart-size bag and then seal.
d. Place the double-bagged ingredients inside the gallon-size bag.
e. Fill the gallon-size bag with ice, pour in the rock salt, squeeze out air, and seal.
f. Gently shake the bag, making sure that the ice is evenly spread out. Continue shaking and kneading the bag gently in your hands.
g. Shake the bag until the mixture solidifies into an ice cream.
h. Remove the smaller bag from the bigger one. Open the bags and eat the ice cream.
2. Access pupils’ prior knowledge. Ask them to identify the states of matter of the materials used in making ice cream, as well as that of the mixture and the ice cream product. Ask the pupils to answer the following questions:
• How did the mixture of cream, vanilla, and sugar become ice cream?
• What was the taste of the cream mixture? the ice cream?
• Was there more heat or less heat when the mixture changed into ice cream?
• Did the composition of the cream mixture change when it became ice cream? Why do you say so?
3. Focus on the following points as you discuss the concepts related to the ice cream making activity:
• The process involved a change in the state of matter: the liquid (cream mixture) turned into solid (ice cream).
• Ice was used to lessen heat and freeze the mixture.
• The similar taste of the cream mixture and the ice cream indicates that the composition of the mixture did not change when it became ice cream.
• The process of making ice cream is an example of physical change.
• Physical change is the change in matter wherein its appearance, form, shape, or size may be altered but its composition stays the same; it does not change into a new substance.
• Matter can change or transform from one state to another through melting, evaporation, condensation, solidification, and sublimation.
4. Let the pupils read the text on pages 30 to 32 of the worktext. Engage them in a discussion about melting, evaporation, condensation, solidification, and sublimation. Give examples for each. Ask the pupils to give other examples of physical changes that they observe in their everyday lives.
Chemical Change
5. Form groups in class. Tell the pupils that they will make an egg sandwich. Prepare the setup for the cooking part of the activity. Instruct the pupils to do the following procedures:
a. Crack the egg and put it in a bowl. Observe the appearance of the raw egg.
b. Scramble the egg using a fork.
c. Add a pinch of salt.
d. Fry the egg in a pan. Observe the appearance of the cooked egg.
e. Remove the cooked egg from the pan. Mix it with mayonnaise.
f. Spread the mixture on a slice of bread and then top with another slice. Eat the egg sandwich.
6. Ask the pupils the following questions after the egg sandwich making activity:
• What was the appearance of the raw egg? the cooked egg?
• How are the raw egg and cooked egg different?
• Can the cooked egg return to having the properties of the raw egg? Why do you say so?
• What did the egg look like after putting mayonnaise?
7. Focus on the following points as you discuss the concepts related to the egg sandwich making activity:
• When the raw egg was cooked, it underwent a chemical change.
• The application of heat (by frying) caused the change in the egg.
• Chemical change is a change that transforms a substance into another, and the transformation cannot be reversed.
• Mixing mayonnaise with egg is a physical change because it can be reversed by washing the mayonnaise off.
• Among the reactions that promote chemical change are combustion, electrolysis, oxidation, and tarnishing.
8. Let the pupils read the text on pages 34 and 35 of the worktext. Engage them in a discussion about the different reactions that cause chemical change in matter. Ask the pupils to give examples of chemical changes that they observe in their everyday lives.
9. Let the pupils investigate the changes that matter undergoes when heat and oxygen is applied or removed. Instruct them to perform Examine activities 1 and 2 on pages 39 to 42 of the worktext. Guide the pupils in doing the activities. Conduct a post-activity discussion to talk about their answers to the guide questions and their conclusions for the activities.
10. Integrate values in the discussion. Emphasize that each individual must always strive to change for the better. Ask the pupils to do the Journal Writing activity on page 38 of the worktext. Let some pupils read their response in class.
1. To motivate the pupils, engage them in an ice cream making activity. Demonstrate and then instruct them to do the following procedures:
a. Pour the all-purpose cream, vanilla, and sugar into a quart-size zip-top bag. Taste the mixture.
b. Squeeze out air and seal the bag tightly. Shake it lightly to mix the ingredients.
c. Place the tightly sealed bag inside another quart-size bag and then seal.
d. Place the double-bagged ingredients inside the gallon-size bag.
e. Fill the gallon-size bag with ice, pour in the rock salt, squeeze out air, and seal.
f. Gently shake the bag, making sure that the ice is evenly spread out. Continue shaking and kneading the bag gently in your hands.
g. Shake the bag until the mixture solidifies into an ice cream.
h. Remove the smaller bag from the bigger one. Open the bags and eat the ice cream.
2. Access pupils’ prior knowledge. Ask them to identify the states of matter of the materials used in making ice cream, as well as that of the mixture and the ice cream product. Ask the pupils to answer the following questions:
• How did the mixture of cream, vanilla, and sugar become ice cream?
• What was the taste of the cream mixture? the ice cream?
• Was there more heat or less heat when the mixture changed into ice cream?
• Did the composition of the cream mixture change when it became ice cream? Why do you say so?
3. Focus on the following points as you discuss the concepts related to the ice cream making activity:
• The process involved a change in the state of matter: the liquid (cream mixture) turned into solid (ice cream).
• Ice was used to lessen heat and freeze the mixture.
• The similar taste of the cream mixture and the ice cream indicates that the composition of the mixture did not change when it became ice cream.
• The process of making ice cream is an example of physical change.
• Physical change is the change in matter wherein its appearance, form, shape, or size may be altered but its composition stays the same; it does not change into a new substance.
• Matter can change or transform from one state to another through melting, evaporation, condensation, solidification, and sublimation.
4. Let the pupils read the text on pages 30 to 32 of the worktext. Engage them in a discussion about melting, evaporation, condensation, solidification, and sublimation. Give examples for each. Ask the pupils to give other examples of physical changes that they observe in their everyday lives.
Chemical Change
5. Form groups in class. Tell the pupils that they will make an egg sandwich. Prepare the setup for the cooking part of the activity. Instruct the pupils to do the following procedures:
a. Crack the egg and put it in a bowl. Observe the appearance of the raw egg.
b. Scramble the egg using a fork.
c. Add a pinch of salt.
d. Fry the egg in a pan. Observe the appearance of the cooked egg.
e. Remove the cooked egg from the pan. Mix it with mayonnaise.
f. Spread the mixture on a slice of bread and then top with another slice. Eat the egg sandwich.
6. Ask the pupils the following questions after the egg sandwich making activity:
• What was the appearance of the raw egg? the cooked egg?
• How are the raw egg and cooked egg different?
• Can the cooked egg return to having the properties of the raw egg? Why do you say so?
• What did the egg look like after putting mayonnaise?
7. Focus on the following points as you discuss the concepts related to the egg sandwich making activity:
• When the raw egg was cooked, it underwent a chemical change.
• The application of heat (by frying) caused the change in the egg.
• Chemical change is a change that transforms a substance into another, and the transformation cannot be reversed.
• Mixing mayonnaise with egg is a physical change because it can be reversed by washing the mayonnaise off.
• Among the reactions that promote chemical change are combustion, electrolysis, oxidation, and tarnishing.
8. Let the pupils read the text on pages 34 and 35 of the worktext. Engage them in a discussion about the different reactions that cause chemical change in matter. Ask the pupils to give examples of chemical changes that they observe in their everyday lives.
9. Let the pupils investigate the changes that matter undergoes when heat and oxygen is applied or removed. Instruct them to perform Examine activities 1 and 2 on pages 39 to 42 of the worktext. Guide the pupils in doing the activities. Conduct a post-activity discussion to talk about their answers to the guide questions and their conclusions for the activities.
10. Integrate values in the discussion. Emphasize that each individual must always strive to change for the better. Ask the pupils to do the Journal Writing activity on page 38 of the worktext. Let some pupils read their response in class.
Generalization and Assessment
1. Do the TOTD assessment. Tell the pupils to identify a dish that they like. Ask: What changes do the ingredients of the dish undergo when the dish is prepared?
2. As enrichment, assign the pupils to practice identifying changes in matter as they play the interactive game on the website provided in Technology Today on page 38 of the worktext.
3. To assess the pupils’ understanding about the changes in matter, ask them to do the exercises in Sharpen Your Skills on pages 35 to 38 of the worktext. Briefly discuss the correct answers.
4. Do the Graffiti Wall activity. Write on the board the terms listed in Use These Words on page 42 of the worktext. Call on pupils to choose one word and then tell something about it.
5. Call on a pupil to summarize the lesson by briefly explaining in his/her own words the concept map in Wrap Up on page 43 of the worktext.
2. As enrichment, assign the pupils to practice identifying changes in matter as they play the interactive game on the website provided in Technology Today on page 38 of the worktext.
3. To assess the pupils’ understanding about the changes in matter, ask them to do the exercises in Sharpen Your Skills on pages 35 to 38 of the worktext. Briefly discuss the correct answers.
4. Do the Graffiti Wall activity. Write on the board the terms listed in Use These Words on page 42 of the worktext. Call on pupils to choose one word and then tell something about it.
5. Call on a pupil to summarize the lesson by briefly explaining in his/her own words the concept map in Wrap Up on page 43 of the worktext.
Performance Task
1. Discuss to the pupils how they should go about the performance task on page 38 of the worktext.
2. Evaluate pupils’ output according to subject content (5 points), video presentation/ creativity (5 points), and organization (5 points).
2. Evaluate pupils’ output according to subject content (5 points), video presentation/ creativity (5 points), and organization (5 points).
Answer Key
Sharpen Your Skills (pages 35–38)
A.
1. freezing
2. solidification
3. evaporation
4. sublimation
5. melting
6. sublimation
7. condensation
8. evaporation
9. freezing
10. evaporation
B.
1. b
2. a
3. b
4. b
5. a
6. c
7. b
8. c
9. b
10. a
C.
1. tarnishing
2. air
3. evaporation
4. new substance
5. water breaking into hydrogen and oxygen
6. bleaching clothes
7. tarnished gold
8. mixing vinegar and baking soda
9. popping bubble gum
10. removing color from nails
1. freezing
2. solidification
3. evaporation
4. sublimation
5. melting
6. sublimation
7. condensation
8. evaporation
9. freezing
10. evaporation
B.
1. b
2. a
3. b
4. b
5. a
6. c
7. b
8. c
9. b
10. a
C.
1. tarnishing
2. air
3. evaporation
4. new substance
5. water breaking into hydrogen and oxygen
6. bleaching clothes
7. tarnished gold
8. mixing vinegar and baking soda
9. popping bubble gum
10. removing color from nails
Examine (pages 39–42)
Activity 1
1. No; the materials reacted differently when they were exposed to heat because they are made of different materials (metal, paper, plastic).
2. The copper wire turned red and became hot to touch. The paper turned black at first and then burned. The plastic bag melted. Heat changes the properties of materials by burning and/or melting.
3. Heat can burn or melt materials.
Conclusion
I learned that different materials react differently when exposed to heat. The materials melt, burn, or become hot.
2. The copper wire turned red and became hot to touch. The paper turned black at first and then burned. The plastic bag melted. Heat changes the properties of materials by burning and/or melting.
3. Heat can burn or melt materials.
Conclusion
I learned that different materials react differently when exposed to heat. The materials melt, burn, or become hot.
Activity 2
1. The materials reacted with oxygen when they were exposed to air. There was a very limited amount of oxygen inside the bag.
2. The apple turned brown and the coin turned yellow to brown. The oxygen in the air reacted with the substances in the apple and the coin, causing oxidation.
3. Oxygen caused chemical reactions with the apple and the coin, thus the change in color.
Conclusion
I learned that oxygen can change the properties of certain materials. Oxygen causes a chemical reaction called oxidation. An evidence of oxidation is the change in the color of substances like apple (turning brown) and coin (turning yellow to brown).
2. The apple turned brown and the coin turned yellow to brown. The oxygen in the air reacted with the substances in the apple and the coin, causing oxidation.
3. Oxygen caused chemical reactions with the apple and the coin, thus the change in color.
Conclusion
I learned that oxygen can change the properties of certain materials. Oxygen causes a chemical reaction called oxidation. An evidence of oxidation is the change in the color of substances like apple (turning brown) and coin (turning yellow to brown).