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BIOLOGY

Phases of Matter

Table of Contents

Lesson 1 – Homogeneous and Heterogeneous Systems .............................................................. 54

Lesson 2 – Pure Substances and Mixtures .................................................................................... 60

Lesson 3 – Types of Mixtures ........................................................................................................ 67

Lesson 4 – Metals and Nonmetals ................................................................................................ 74

Lesson 5 – Acids, Bases, and Salt .................................................................................................. 79

Lesson 6 – Organic and Inorganic Compounds ............................................................................. 85

Lesson 7 – Useful Elements and Compounds ............................................................................... 92

Lesson 8 – Industrial Elements and Compounds .......................................................................... 98

Lesson 9 – Methods of Separating Mixtures .............................................................................. 103

Lesson 10 – Mixture Preparation and Recovery ......................................................................... 108

Unit 1- Rediscovering the World of Chemistry

Chapter 2 Phases of Matter

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Lesson 1

HOMOGENEOUS AND HETEROGENEOUS SYSTEMS TIME

Two sessions SETTING

Classroom/laboratory

OBJECTIVES

At the end of this session, the students should be able to:

state and identify the number of phases in a chemical system;

differentiate operationally a homogeneous from a heterogeneous chemical system;

classify a chemical system as homogeneous or heterogeneous;

observe and record data involving chemical systems, and;

make inferences. PREREQUISITE

Students should have prior knowledge on the use of laboratory

instruments and performing mathematical operations.

RESOURCES

soy sauce mud salt

garlic calamansi 8 test tubes

vinegar flour graduated cylinder

cooking oil starch teaspoon

water syrup test tube rack



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PROCEDURE

Opening Activity

Begin the session by asking the class:

What is your usual breakfast? I am sure your breakfast consists of hot coffee and “pan de sal”. Sometimes you might even put sandwich spread or cheese spread on the bread. What do you observe when you prepare your coffee and sandwich?

Main Activity CHEMICAL SYSTEMS

1. Divide the class into small groups.

2. Clarify objectives and procedures.

3. Present materials that will be used in the activity.

4. Give precautionary measures.

5. Let the students do the activity on “Chemical Systems”. Refer to the activity sheet.

Teacher Notes

Descriptions of Chemical Systems

1. soy sauce black with characteristic odor

1 homogeneous

2. garlic in vinegar

white with characteristic odor

2 heterogeneous

3. cooking oil in water

yellow-colorless

odor varies 2 heterogeneous

4. mud and water

blurred with characteristic odor

2 heterogeneous

5. filtered calamansi

yellow with characteristic odor

1 homogeneous

6. flour and starch

white odorless 1 homogeneous

7. syrup color varies

odor varies 1 homogeneous

8. salt water solution

colorless odorless 1 homogeneous



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Closing Activity

Ask students to differentiate a homogeneous from a heterogeneous system:

1. A homogeneous system is a one-phase system where all parts show the same characteristics/properties throughout.

2. A heterogeneous system consists of one or more phases where each part retains its original properties.

ASSESSMENT

A. Classify the following as either homogeneous or heterogeneous

1. powder detergent (Ans: Heterogeneous)

2. cement (Ans: Homogeneous)

3. concrete (Ans: Heterogeneous)

4. fish “bagoong” (Ans: Heterogeneous)

5. bottled soda (soft drinks) (Ans: Homogeneous)

6. wood varnish (Ans: Homogeneous)

7. fruit salad (Ans: Heterogeneous)

B. How many phases can be seen after mixing the following systems?

1. garlic, vinegar, salt, pepper (Ans: 3)

2. flour, baking soda, egg yolk, water (Ans: 1)

3. cooking oil and vinegar (Ans: 2) HOMEWORK

Our environment provides us with naturally occurring chemical systems like water, soil and air, which may be homogeneous or heterogeneous. Water plays an important role not only in life processes, but also in the environment. We grow our plants in soil, which gives us clean air. People throw much waste into these systems and find themselves affected by this careless behavior.

1. Can you suggest ways by which we can safeguard the environment, particularly water, soil and air in order to maximize their uses?

2. Which of the suggestions given do you find easier to do? Why?



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REFERENCES

Soriano, Santisteban, Elauria. Chemistry for the New Millennium. Metro Manila, Philippines: Adriana Publishing Co. Inc. 37.

Rabago, Mapa, Fidelino. Science and Technology, Chemistry. Metro Manila: S.D. Publishing Publications, 40.

Science and Technology III. Philippines: Cacho, Hermanos, Inc. 31.



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Student Activity 1

CHEMICAL SYSTEMS

OBJECTIVES

In this activity, you will:

state and identify the number of phases in a chemical system;

differentiate a homogeneous from a heterogeneous chemical system operationally;

classify each chemical system as either homogeneous or heterogeneous; and,

observe and record data involving chemical systems.

RESOURCES

soy sauce mud salt

garlic “calamansi” 8 test tubes

vinegar flour graduated cylinder

cooking oil starch teaspoon

water syrup test tube rack PROCEDURE

1. Number the test tubes 1 to 8.

2. Put each sample material into a separate test tube

3. Observe the materials’ properties in terms of color, odor, number of phases and appearance

4. Classify the chemical system as either homogeneous or heterogeneous.

5. Record and tabulate your observations.



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Chemical System Color Odor Number of Phases

Homogeneous/

Heterogeneous

1. soy sauce

2. garlic in vinegar

3. cooking oil in water

4. mud and water

5. filtered calamansi

6. flour and starch

7. syrup

8. salt water

solution

GUIDE QUESTIONS

1. How many phases did you see in each set-up?

2. Which systems were homogeneous? Heterogeneous?

3. How would you define a homogeneous system? A heterogeneous system?



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Lesson 2

PURE SUBSTANCES AND MIXTURES TIME

Two sessions

SETTING

Classroom/laboratory OBJECTIVES

At the end of this session, the students should be able to:

differentiate between pure substances and mixtures;

determine whether a chemical system is a substance or a mixture;

distinguish between the properties of substances and those of mixtures.

PREREQUISITE

Students should have prior knowledge on homogeneous and heterogeneous systems.

RESOURCES

table salt iron filings sulfur

alcohol lamp glass plate magnet

water

oil

powdered naphthalene

wire gauze

iron stand

spoon

test tube iron ring tongs

cover of powdered milk aluminum foil tripod

medicine dropper ammonium chloride match



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PROCEDURE

Opening Activity

Show to the class a glass of water and 3-in-1 coffee dissolved in hot water. Ask them to distinguish the two liquids. What difference do you notice between drinking water and drinking

3-in-1 coffee? Which is a substance? A mixture?

Main Activity “IS IT PURE OR MIXTURE?”

1. Divide the class into seven groups.




5. Let the students do the activity on “Pure Substances and Mixtures”.

Key Learning Points

Pure substances contain only one type of matter, have a definite or constant composition, and exhibit consistent behavior in chemical reactions.

Examples include water, oxygen, dry ice and ammonia. Mixtures contain two or more substances combined in such a way

that the properties of the components are retained and distinguishable.

Examples of mixtures are milk, cement, air and fruit salad. Closing Activity

Ask students to present the key points of the lesson by drawing a concept map such as drawn below.

A substance is a homogeneous material consisting of one particular kind of matter.

A mixture is material consisting of two or more kinds of matter, each of which retains its own characteristic properties.



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ASSESSMENT

Write the letter of the correct answer. 1. A white solid turns into black solid and white smoke when heated.

What is the white solid?

a. element b. substance c. mixture

2. A form of matter which cannot be separated into different components by ordinary means.

a. element b. substance c. mixture

3. It is composed of two or more components that are physically combined.

a. substance b. mixture c. molecule

4. A mixture can be separated through

a. chemical means b. use of electric current c. filtration

5. Which of the following is a mixture?

Matter

can be described as

Heterogeneous (2 or more phases)

Homogeneous (single phase)

Mixtures Substances

Variable Properties

Constant boiling and melting points

is always classified as

can be separated into

have have



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a. lead b. brass c. charcoal

NOTE! Answers are typed in bold and /underlined letters



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HOMEWORK

1. What are the three types of mixtures?

2. What are the different properties of mixtures? REFERENCES

Rabago, Mapa, Fidelino. Science and Technology Chemistry. 1999. Metro Manila, Philippines: SD Publications Inc. 40–42.

Soriano, Santisteban, Elauria. 2000. Chemistry for the New

Millennium. Philippines: Adriana Publishing Co., Inc. 42.



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Student Activity 2

IS IT PURE OR MIXTURE?

OBJECTIVES

In this activity, your team will:

differentiate between pure substances and mixtures;

determine whether the chemical system is a substance or a

mixture;

distinguish between the properties of substances and mixtures;

RESOURCES

table salt iron filings aluminum foil

alcohol lamp tong magnet

water

oil

powdered naphthalene

sulfur

iron stand

spoon

test tube iron ring glass plate

cover of powdered milk

wire gauze

ammonium chloride

tripod

match

medicine dropper

PROCEDURE

1. Mix iron filings and sulfur on a glass plate. Observe their appearance and hold a magnet over them. What happens?

2. Mix iron filings and sulfur on a sheet of aluminum foil. Heat the mixture and let cool. Observe its appearance. Hold a magnet over it. What happens?

3. Heat 3 ml of water in a test tube until it boils. For 3 minutes, record the temperature every 30 seconds. Heat further. Observe what happens to the water.

4. Heat 3 ml of salt solution in a test tube until it boils. For 3 minutes, record the temperature every 30 seconds. Heat the solution further. Observe what happens to the water.



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5. Half-fill a test tube with water. Half-fill another test tube with oil and water. Observe the appearance of the liquid in each test tube. Count the number of phases per test tube.

6. Place a pinch of naphthalene in a clean, dry spoon. Heat the spoon with naphthalene over flame. Record the time at which the naphthalene starts to melt until the time it is completely melted. Heat again for another 5 minutes. Describe what happens.

7. Place a pinch of powdered naphthalene and a pinch of NH4Cl solids in a clean dry spoon. Heat the spoon over flame. Record the time the naphthalene starts to melt until it has completely melted. Heat for another 5 minutes. Describe what happens.

8. Mix a pinch of powdered naphthalene and a pinch of iron filings in another spoon. Observe the appearance of the mixture. Then heat the mixture over the flame of the alcohol lamp for 5 minutes. Describe what happens.

GUIDE QUESTIONS

1. Can you separate the components of unheated iron filings and sulfur? What about the heated iron filings and sulfur? How would you classify each system?

2. How would you describe the boiling temperature of the salt solution?

3. Were you able to separate the components of water? Were you able to separate the components of the salt solution?

4. How many phases were observed in the test tube half-filled with water? What about in the test tube half-filled with oil and water? How would you classify each system?

5. How would you describe the melting point of powdered naphthalene and ammonium chloride? Which system has a sharp melting point? Which melts at a temperature range? How would you classify the two systems?

6. When the powdered naphthalene was heated further, what was left on the spoon? When the powdered naphthalene and sulfur were heated for 5 minutes, what was left on the spoon? How would you classify the system?



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Lesson 3

TYPES OF MIXTURES

TIME

One session SETTING


OBJECTIVES

At the end of the session, students should be able to:

enumerate and describe the three types of mixtures;

prepare different types of mixtures;

give examples of solutions, suspensions, and colloids; and,

classify mixtures based on their properties.

PREREQUISITE

Students should have prior knowledge on homogeneous and heterogeneous substances.

RESOURCES

a small cassava tuber (“kamoteng kahoy”)

2 small glass bottles of the same size

funnel wire gauze

2 sheets of cardboard knife

tripod 10g refined sugar

penlight or flashlight balance

filter paper or cheese cloth 50 ml water

alcohol lamp graduated cylinder PROCEDURE

a. Review the previous lesson:

Material substances can be divided into two classes.

Substances such as water and gasoline that appear uniform

throughout are called homogeneous substances, which can be

subdivided further into pure substances and solutions.



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A pure substance is a homogeneous material consisting of one

particular kind of matter. It can either be an element or a

compound.

A solution, on the other hand, is a homogeneous mixture like

sugar dissolved in coffee, or iodine dissolved in alcohol (tincture

of iodine).

A mixture can contain two or more different components in

varying proportions. A mixture that consists of two or more

visibly different homogeneous components, such as oil floating

in water, is heterogeneous.

The different homogeneous portions in a heterogeneous mixture

are sometimes called phases.

For example, a mixture of mercury, water and oil consists of

three different liquid phases. A rusty iron nail consists of two

different phases of the solid state: the unrusted iron and rust (an

iron oxide).

b. Ask the students to list as many mixtures as they can and let them share their answers. Lead the discussion by saying:

At home we prepare several mixtures. Gelatin is one good

example. This dessert is prepared by simply mixing “gulaman”

(agar-agar) bars with water and sugar. Milk chocolate, coffee, fruits

or a combination of these ingredients may be added to produce the

desired flavor. Gelatin is thus a mixture of various ingredients.

Many of your other favorite foods like candy, ice cream, cake, coco

jam, peanut butter, fruit jelly, halo-halo (a refreshment made up of a

mixture of beans, jackfruit, banana and ice cream), “ginataan” (a

native food cooked in coconut milk) and “palabok” (a noodle dish)

are examples of mixtures. Other familiar mixtures include vinegar,

soy sauce, herbal medicines, and hand and body lotion.



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Main Activity INVESTIGATING MIXTURES

1. Divide the class into seven groups.




5. Let the students investigate the properties of mixtures. Refer to the attached activity sheet.

Teacher Notes

The different components in a suspension may be seen with your

naked eyes because they have mass. The suspended particles

tend to settle down and filter easily. However, in suspensions, the

path of light cannot be seen because the particles are too big to

disperse light. There are two or more phases in a suspension.

Solutions are homogeneous mixtures with only one phase. The

particles are too small to be seen by the naked eye and are thus

unable to scatter light. Solution particles are small enough to pass

through the pores of filter paper.

Colloids contain particles bigger than those in solutions, but smaller

than those in suspensions. Colloid particles can only be seen by

means of an ultra microscope. These particles remain indefinitely

suspended in the medium and cannot be filtered by ordinary

means. Colloidal particles are of the right size to scatter light. We

call this light-scattering phenomenon of colloids the Tyndall effect.

This Tyndall effect enables you to see the path of light in colloids.

Closing Activity

The types of mixtures: solutions, colloids, and suspensions - can be compared and differentiated based on their properties: filterability, number of phases, degree of settling, particle size and their ability to scatter light (Tyndall effect).



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ASSESSMENT

Ask the students to classify the following chemical systems into solutions, colloids and suspensions.

1. vinegar (Ans. solution)

2. mayonnaise (Ans. colloid)

3. milk (Ans. colloid)

4. spaghetti sauce (Ans. suspension)

5. chocolate drinks (Ans. suspension)

HOMEWORK

Give other examples of mixtures and describe how each may be classified.

REFERENCES

Lianko, A. 1996. Science and Technology III Chemistry. Quezon City: FNB Educational Inc. 27–28.

Science and Technology III. SEDP Series. 30–34.



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Student Activity 3

INVESTIGATING MIXTURES OBJECTIVES


prepare different kinds of mixtures;

describe a mixture based on its properties;

give examples of solutions, suspensions, and colloids. RESOURCES

a small cassava tuber (“kamoteng kahoy”)

2 small glass bottles of the same size

funnel wire gauze

2 pcs. of cardboard knife

tripod 10g refined sugar

penlight or flashlight balance

filter paper or cheese cloth 50 ml water

alcohol lamp graduated cylinder PROCEDURE

Process A

a) Cut the cassava tuber into tiny cubes. Put the cubes in a bottle.

Add water and stir the mixture. Describe what happens.

b) Filter the mixture. Set the filtrate (the filtered liquid) aside.

Process B

a) Put the sugar in another bottle. Add water and stir.

b) Filter the mixture.

c) Get two sheets of cardboard.

1. Bore a hole through one piece. The diameter of the hole

should be smaller than the diameter of the flashlight or

penlight head.



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2. Position the flashlight/penlight between the two cardboards, and

put the test bottle in a straight line as shown in the figure below.

3. Place the test solution along the path of light. Let the light beam

from the flashlight pass through the hole of the cardboard. Look

at the solution at a right angle to the direction of light. Move the

flashlight up and down. Which mixture is the solution? The

colloid?

Process C

a) Get the filtrate that you set aside in Procedure A (b). This filtrate

contains cassava starch. Set aside ¼ of the volume of the

filtrate. Add as much water to it to dilute the filtrate three times.

Then transfer the diluted filtrate to a bottle.

b) Apply heat to the diluted filtrate for 3 minutes. Let it cool.

c) Filter the mixture using a filter paper or cheesecloth.

d) Repeat the test for scattering light, Procedure B (c), on the

filtrate.



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Data Table

Properties

Raw Cassava Cubes and

Water

Sugar in

Water

Cooked Cassava Starch

in Water

1. Visibility of particles

2. Number of phases

3. Ability of particles to settle down

4. Ability of particles to be filtered

5. Ability of particles to scatter light

6. Type of mixture

GUIDE QUESTIONS

1. How would you describe a solution, a colloid, and a suspension?

2. In what aspects are solutions and colloids similar? Different?

3. In what aspects are suspensions and colloids similar? Different?

4. Which mixture exhibited the Tyndall effect?



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Lesson 4

METALS AND NONMETALS TIME

Two sessions SETTING Classroom/laboratory OBJECTIVES

At the end of the session, students should be able to:

distinguish metals from nonmetals;

classify elements as metals or nonmetals based on their properties;

perform tests to identify metallic and nonmetallic elements. PREREQUISITE

Students should have prior knowledge on the difference between elements and compounds.

RESOURCES

carbon rod sulfur powder

lead (“tingga”) copper wire

hammer alcohol lamp

match

PROCEDURE

Opening Activity

Begin the session by asking the class:

a. What can you remember about the activity on “electrolysis”?

b. What elements are found in water?

c. Would you have any idea about the states of matter obtained?



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Main Activity METALLIC VS. NON-METALLLIC

1. Divide the students into small groups.

2. Clarify the objectives and procedures.

3. Prepare the materials.

4. Review precautionary measures.

5. Have the students do the activity on metals versus nonmetals. Refer to the attached activity sheet.

6. Ask the different groups to report their findings to the class.

Key Learning Points

a. Metals are ductile, malleable, and lustrous. They are good

conductors of heat and electricity. Some metals like silicon are

used as semiconductors.

b. Nonmetals are brittle and are poor conductors of heat and

electricity. Nonmetals are used in the production of chemicals,

including fertilizers, bleaches and detergents.

Closing Activity

Copper wire and lead are examples of metals. They are lustrous, malleable and good conductors of heat and electricity.

A carbon rod and sulfur are nonmetals. They have no metallic luster, are brittle and are poor conductors of heat and electricity.

ASSESSMENT

Assess the students based on the following rubrics:

5 – exceptionally well done/cooperation of the group was observed

4 – accurate and detailed explanation

3 – partially detailed information

2 – less information/ knowledge shared

1 – not well done



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HOMEWORK

Gold panning is common in many parts of the Philippines. It is the simplest method of extracting gold from mixtures. The people of Baguio, Davao and Surigao developed this method as a source of income. To do this, each citizen cooperates and tries to be more productive. If you happened to be in any of the three communities, in what way do you think can you help your family?

REFERENCES

Rabago, Mapa, Fidelino. 1999. Science and Technology Chemistry. Metro Manila, Philippines: SD Publications, Inc. 45–46.


Soriano, Santisteban, Elauria. 2002. Chemistry for the New Millennium. Philippines: Adriana Publishing Co. Inc. 43–44.



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Student Activity 4

METALLIC VS. NON-METALLIC OBJECTIVES


compare and contrast metals from nonmetals;

classify the given elements as either metals or nonmetals based on their properties.

RESOURCES

carbon rod sulfur powder

lead (“tingga”) copper wire

hammer alcohol lamp

match

PROCEDURE

1. Get a carbon rod, a pinch of sulfur powder, lead and a 15-cm copper wire without an insulator.

2. Observe the appearance of each. Which of them has luster?

3. Holding one end of the copper wire, heat the other end for a few seconds. Do likewise with the rest. Which of them transmits heat?

4. Hammer all elements. What happens to each?

5. Write your observations in the table below.

6. Report your findings to the class.

Properties Carbon Rod

Sulfur Rock

Copper Wire

Lead

Has luster/dull

Heat conductor/ Nonconductor

Malleable/brittle



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GUIDE QUESTIONS

1. Which of the materials show luster?

2. Which of them transmit heat?

3. What happens to the substances when you hammer them?

4. Which of the substances are metal? Which are nonmetals?

5. How can you distinguish metals from non-metals?



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Lesson 5

ACIDS, BASES AND SALT

TIME



OBJECTIVES

At the end of the session, the students should be able to:

perform tests using indicators to distinguish acids, bases and salts.

differentiate an acid, base and salt based on their reactions to the indicators;

appreciate the importance of acids, bases and salts as applied to our daily life.

PREREQUISITE

Students must have prior knowledge of the different characteristics of

metals and non-metals.

RESOURCES

vinegar, soap (any), calamansi juice, lime water (“apog”), “salitre”,

aspirin, fertilizer, toothpaste, milk of magnesia

litmus paper

phenolphthalein or plant pigments

15 vials or “tansan”

water



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PROCEDURE

Opening Activity

1. Discuss the concept of compounds.

Compounds are pure substances made of atoms of two or more

elements chemically combined in fixed ratios. Sugar and table

salt are examples of compounds that can be easily identified by

their taste. Though tasting is a means of identifying substances,

there is another method where indicators are used. Indicators

are neutral substances that show different reactions in acidic

and basic solutions.

Some compounds are not safe to taste; thus, it is necessary to

take precautionary measures in attempts to identify them.

2. Discuss the objectives of the activity. Remind the students not to taste any of the materials unless they are told to do so.

3. Prepare mango, “alamang”, table salt and lye in different containers.

4. Ask the students to smell and taste each of the items and to describe the items based on their texture, taste and smell.

Main Activity HOUSEHOLD ACIDS AND BASES

1. Divide the students into small groups.

2. Clarify the objectives and procedures.

3. Prepare the materials.

4. Review precautionary measures.

5. Have the students perform the activity on household acids, bases and salts. See Student Activity No. 5.

6. Ask the different groups to report their findings to the class.

7. Facilitate class discussion using the guide questions. Elicit and summarize the key learning points from the students’ observations, analysis and discoveries.



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Key Learning Points

Acid tastes sour and changes blue litmus paper to red.

Examples

acetic acid in vinegar

citric acid in “calamansi”

acetyl salicylic acid in aspirin

carbonic acid in carbonated drinks

A base is a compound that is bitter and slippery to the touch. It changes red litmus paper to blue.

Examples

Sodium hydroxide (lye) for soap-making

Calcium hydroxide or lime water

Magnesium hydroxide or milk of magnesia

Aluminum hydroxide in antacid

Salt is the substance formed when the hydrogen of an acid is

partially or wholly replaced by an active metal. Examples:

Sodium nitrite or “salitre” as food preservative

Sodium fluoride in tooth decay

Potassium carbonate in fertilizer

Calcium carbonate or limestone

Indicators are substances that exhibit a specific color in the

presence of acids and bases.

Closing Statement

To determine whether a substance is an acid, base or salt, methods

such as tasting, checking its reaction with litmus paper,

phenolphthalein, and pH range can be used. In other instances,

chemical tests and analysis can also be done in the laboratory.



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ASSESSMENT

A. Identify whether the following substances are acids, bases or salts.

1. saliva

2. detergent

3. potash

4. guava

5. baking powder

B. Explain why aspirin must not be taken in with an empty stomach.

HOMEWORK

1. Divide the class into small groups. Ask the students to:

research on the following topics: vinegar making, salt making and soap making, and;

conduct an experiment on any of the three topics at home.

2. Remind them that they are expected to:

report on their experiment in class, and;

read the assigned article entitled “Organic and Inorganic Compounds”.

REFERENCES

Espana, Salmorin. Science and Technology III. 268–271. Rabago Mapa, Fidelino. Science and Technology III. 48–50.



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Student Activity 5

HOUSEHOLD ACIDS AND BASES OBJECTIVE

In this activity, your team will perform tests using indicators to distinguish acids, bases and salts.

RESOURCES

15 vials or “tansan”

Indicators (litmus paper, phenolphthalein)

Household materials:

vinegar, soap (any), “calamansi” juice, lime water (“apog”), “salitre”,

aspirin, fertilizer, toothpaste, limestone, milk of magnesia

PROCEDURE

1. Observe the household materials in terms of color, odor, and taste.

Write down your observations on the table below.

CAUTION! Not all materials can be tasted. Ask the teacher for

guidelines.

2. Test the reaction of the household materials on litmus paper and

using the phenolphthalein indicator. Dissolve solid samples in a

small amount of water (tap or distilled). Measure 3–4 drops of liquid

samples.

3. Enter all reactions in the table below.

4. Assign a group leader to present the observations of the group.



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Household Materials

Properties Color Change with Litmus or

Phenolphthalein

Name of Acid, Base,

and Salt Present

Color Odor Taste

1. vinegar

2. soap

3. calamansi juice

4. lime water

5. milk of magnesia

6. salitre

7. aspirin

8. fertilizer

9. toothpaste

10. limestone

GUIDE QUESTIONS

1. How did the household materials react with litmus paper and

phenolphthalein? What do you think are the common reactions of

acids, bases and salts in these indicators?

2. What common properties are present in acids, bases, and salts?

3. In your opinion, how are acids/ bases neutralized?



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Lesson 6

ORGANIC AND INORGANIC COMPOUNDS

TIME


Classroom/laboratory OBJECTIVES


define organic and inorganic compounds;

differentiate organic from inorganic substances using formulas;

classify compounds as organic or inorganic, and;

discuss the importance of organic compounds. PREREQUISITE

1. The students should have prior knowledge on acids, bases, and salts.

2. Students should be able to present their research on vinegar making, salt making and soap making.

RESOURCES

chart showing formulas of some compounds

matches

ice cubes

small candle

white ceramic plate

galls jar or beaker



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PROCEDURE

Opening Activity

a. Ask students to look at the formulas of the compounds shown below. What do the formulas posted on the board have in common?

Aspirin C9H8O4 Acetylsalicylic acid

C6H4(OCOCH3)CO2H

Plastic (CH2-CHCl)n Polyvinyl chloride (CH2=CHCl)

Gasoline (C8H18) Methanol (CH3OH)

Alcohol (CH3CH2OH) Ethyl alcohol (CH3CH2OH)

Vinegar (CH3COOH) Acetic acid (CH3COOH)

b. Have a class discussion on organic compounds:

The element carbon is found in all organic compounds. It is always

in combination with hydrogen, oxygen, nitrogen and other

elements. However, not all compounds containing carbon are

classified as organic. There are some compounds containing

carbon, which are classified as inorganic, because their chemical

behaviors resemble the characteristics of this group more.

Inorganic carbon compounds include carbides like calcium carbide

(CaC2), carbonate like magnesium carbonate (MgCO3), and

cyanide like potassium cyanide (KCN).

Therefore, organic compounds are those that contain carbon while

inorganic compounds are non-carbon compounds.

Main Activity ORGANIC VS INORGANIC SUBSTANCES

a. Divide the students into small groups. Give them copies of the activity sheet. Clarify the objectives of the activity.

b. Each group will report their findings to the class. Facilitate class discussion using the guide questions. Elicit and summarize the key learning points from the students’ observations, analysis and discoveries.



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Discussion Ideas

The candle melts and liquid is drawn up into the wick where it burns with air.

The black deposit that appeared on the white ceramic plate is carbon.

The candle is slowly extinguished when covered with a beaker. Condensed water droplets appear on the inside of the beaker. The candle wax is either beeswax or paraffin (wax from oil). The elements present in paraffin are Cn H2n+2,where n is the number of carbon atoms that is greater than 20.

Organic things will burn easily. Inorganic things will generally not burn. Certain inorganic things will burn if they get hot enough.

Inorganic chemicals do not burn because of their chemistry. Soil is a special case. Soil is a mixture of both organic and inorganic things. The organic things in soil may burn (the grass, wood, etc.), but will eventually burn itself out because the rest of it is inorganic (minerals, rocks, etc.).

Key Learning Points

How do you know that a substance is organic/inorganic? What are the characteristics of organic and inorganic compounds? Where do we usually find these compounds?

Organic substances are compounds that contain the element carbon attached to itself and to hydrogen. Carbon's special ability to bond to vast numbers of other carbons makes an almost unlimited number of compounds possible. Organic compounds are found in all living organisms and from the remains of plants and animals.

Examples of organic compounds are foods (sugar starch, fats, proteins and carbohydrates), fuels (petroleum), wood, paper, fabrics, plastics, dyes, paints, cosmetics, drugs, medicines, insecticides, herbicides, soaps, and detergents.

Inorganic substances are the compounds of all elements other than carbon. These compounds are usually found outside the bodies of living things. Examples of inorganic compounds include rust, sand, table salt, water, muriatic acid, carbonate and hydroxides.



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Closing Statement

Naturally occurring organic compounds have important biological functions. They include fats, protein, carbohydrates, vitamins, cellulose, enzymes and hormones. Most synthetic organic compounds have important practical uses. They are used as fuels, clothing, medicine, cosmetics, detergents and chemicals for agricultural use and in industries.

ASSESSMENT

Classify the following compounds as organic or inorganic. Write O for organic and I for inorganic opposite each compound.

HOMEWORK

1. Plastic is a non-biodegradable substance. It clogs the sewage system and is one of the causes of floods. Ask each group to propose a project on recycling plastic.

2. What elements and compounds are basic to our daily life? Ask the students to cite the elements or compounds found in the food they eat and in the things that they use at home or in school.

REFERENCES

Boni, Milagros. Science and Technology III. PSSLC. 30–31.

Magno, Punzalan, Tan. Science and Technology for a Better Life. 36.

Rabago Mapa, Fidelino. Science and Technology III. 48.

http://www.noacsc.org/allen/ac/sesa/handbook_files/ScienceTalk2004.doc

___table salt ___soap

___acetone ___ethyl alcohol

___magnesium carbonate ___muriatic acid

___aluminum hydroxide ___polyester

___toiletries (toothpaste, shampoo, soap)

___sulfuric acid



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Student Activity 6a

ORGANIC VS INORGANIC SUBSTANCES (Option 1) OBJECTIVE

In this activity, your team will differentiate organic from inorganic substances.

RESOURCES

1 small candle

matches

a white ceramic plate PROCEDURE

1. Light the candle.

2. Place a ceramic plate on top of the candle flame for a few seconds. Remove the plate and observe its bottom.

3. Invert the beaker over the flame and place an ice cube on top of it.

4. Record all observations and discuss these with your group mates.

Observations

Ceramic Plate

Beaker

GUIDE QUESTIONS

1. What happened to the candle when it was lighted?

2. What did you observe when the ceramic plate was placed over the candle flame? What is the composition of these substances?

3. What happened inside the beaker when it was placed over the flame?

4. What are these droplets made up of? What elements are present in the paraffin?

5. How will you differentiate organic from inorganic compounds?

ice cubes

a beaker



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Student Activity 6b

ORGANIC VS. INORGANIC BURNING (Option 2)

OBJECTIVE

In this demonstration activity, you will differentiate organic from inorganic substances through combustion (the ability to burn something).

RESOURCES

matches candles cotton cloth polyethylene plastic

(softdrink) bottle nail polish remover

SAFETY

Have a tray of water available to put out matches, etc., but not for magnesium.

PROCEDURE

PART 1 ORGANIC BURNING

1. Place a candle in the soft-drink bottle. Light a match. Explain that the match is made from a mixture of chemicals to get it to light and catch the wood/paper on fire.

2. Light the candle. Observe what happens to the candle wax.

3. While the candle is burning, cut off a small piece of cotton cloth and see if it burns.

4. While the candle is burning, cut off a small piece of polyethylene plastic film and see if it burns.

5. Add a tiny drop of nail polish remover to a beaker. Be sure to close the bottle of nail polish remover and remove from the area. Take a match and light the nail polish remover that is in the beaker. This is how gasoline burns and how an engine gets the power to run a car.

soil salt safety glasses/goggles tongs watch glass magnesium ribbon



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PART 2 INORGANIC BURNING

1. While the nail polish remover is burning, dump some soil into the

beaker. Observe what happens to the soil.

2. Using the salt shaker, sprinkle salt on to the candle and the flame will go out. The flame goes out because the salt does not burn. The salt smothers the fire due to lack of air.

3. With the candle burning, try to ignite a piece of aluminum foil. You may notice that the foil may melt (melting point of aluminum is

1220F), but it does not burn.

Special Cases

Certain metals, if heated up intensely, will burn.

Safety glasses/goggles are required for this experiment.

Demonstrate with a piece of Magnesium ribbon. Cut a piece of Magnesium ribbon no more than 1 inch long. Have a watch glass available. Hold the ribbon with tongs.

Place the ribbon into the candle fire. The Magnesium is relatively stable as a solid, but when it melts, the magnesium will ignite and burns with a dazzling white flame (rapid oxidation).

GUIDE QUESTIONS

Which substance burned easily?

Which substance did not burn?

Which substance was burned when they get hot enough?

How will you differentiate organic from inorganic compounds?



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Lesson 7

USEFUL ELEMENTS AND COMPOUNDS

TIME



OBJECTIVES


identify elements and compounds which are basic to our daily lives

cite the importance of elements and compounds

PREREQUISITE

Students should have basic knowledge and skills to:

differentiate between organic and inorganic compounds;

discuss the proposed project or plan of each group on recycling

plastic.

RESOURCES

bond paper

pens or pencils

PROCEDURE

Opening Activity WORD CHOP

a. Begin the session with a simple brainteaser. Ask students to answer questions on Activity Sheet 7a. Then proceed with the definition of terms.

b. Help the students clarify the difference between elements and compounds.



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Pure substances have an invariable composition and are composed of either elements or compounds.

Elements are "substances which cannot be decomposed into simpler substances by chemical means".

Compounds can be decomposed into two or more elements by chemical reactions.

Main Activity HUNTING FOR ELEMENTS AND COMPOUNDS

1. Divide the class into 10 groups.

2. Distribute the activity sheets to the different groups.

3. Be sure that each group has one copy of Activity Sheet B.

4. Ask each group to list as many elements and compounds as possible, and to indicate the uses of each.

5. Ask each group to write their list on the board. Guide Questions

1. What are the most common elements? Compounds?

2. What is the significance of the fact that some elements appear in more than one common compound?

3. Why are some elements so rare, while others appear frequently?

4. What are the roles of elements and compounds in man’s daily life?

Key Learning Points

a. Pure substances are divided into two: elements and compounds.

Most of the time, the various elements and compounds in different

substances are seen as whole items rather than as different

elements.

b. Elements and compounds play critical roles in our daily life as

follows:



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Elements and

Compounds Importance and Functions

Calcium Facilitates the development of bones and teeth and the regulation of blood clotting and muscle action.

Phosphorous Promotes the development of bones and teeth.

Copper Helps in the formation of hemoglobin.

Potassium Maintains regular heartbeat, water balance and cell integrity.

Sodium Important in nerve reduction and fluid balance.

Magnesium Serves as a catalyst in the synthesis of energy-carrier molecules.

Oxygen Responsible for the burning of food in animals; it is the product of photosynthesis in plants.

Water Helps eliminate toxins from the body.

Carbon dioxide Absorbed by plants when they make food.

Sugar Used in food preservation.

NOTE! The above substances have other important functions other

than the listed ones.

Extension Ideas EVERYDAY COMPOUNDS Water might be the most common compound on Earth. As almost

everyone knows, two atoms of the element hydrogen (H) plus one

atom of the element oxygen (O) make one molecule of water (H2O).

Many other everyday substances are found in almost anyone’s

kitchen or bathroom. Ask your students to make a list of

substances found in their homes that they believe are

compounds. Their list might include sugar, salt, baking soda,

hydrogen peroxide, and ethyl alcohol, among many others.

Then ask each student to choose one of these compounds and conduct a basic research to determine what elements it is composed of. Make sure that each student chooses a different compound to generate as wide a variety of topics as possible.



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When research is complete, have each student prepare a brief

presentation for the class on what she or he has discovered. Each presentation should include a detailed sketch of the compound’s elemental structure.

Conclude with a discussion about the most common elements contained in the various compounds that the students have presented.

Closing Activity HUNTING FOR NEW ELEMENTS

Lead a brief discussion about the discovery and creation of new elements. In part for her discovery of the elements radium and polonium, Marie Curie won the Nobel Prize for chemistry in both 1903 and 1911—no small feat. Discovering new elements today, however, is a much more challenging endeavor. Scientists must go to tremendous lengths in the laboratory to actually create elements, often by bombarding atoms of one element with atoms from another.

Is the discovery or creation of a particular element an important endeavor? What potential benefits does the hunt for new elements offer to the human race?

ASSESSMENT

Evaluate the students based on the number of correct elements and compounds they listed.

HOMEWORK

Ask the students to study the labels of common products and to note their composition.

What are some of the elements and compounds which are of relative importance to our economy?

REFERENCES

Bon, Milagros. Science and Technology III PSSLC. 31.

Department of Education Region IV-A. Chemistry. 53.

Fidelino, Mapa, Rabago. Science and Technology III. 47–48.

Mendoza, Religioso. Chemistry. 20–21.

http://school.discovery.com/lessonplans/programs/elementsandcompounds/

http://www.teach-nology.com/worksheets/science/element/chop/

http://school.discovery.com/lessonplans/programs/elementsandcompounds/

http://www.teach-nology.com/worksheets/science/element/chop/



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Student Activity 7a

WORD CHOP

Direction

The table below contains words that have been chopped in half. Find the pieces that fit together and write them on the spaces provided.

ture sym mole ment

rons comp ound sity

prot bol ele den

trons mix neut ume

rons cule elec vol

Answers

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________

________________________



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Student Activity 7b

HUNTING FOR ELEMENTS AND COMPOUNDS

OBJECTIVE

In this activity, your team will enumerate the basic elements and compounds, which are necessary for living organisms.

PROCEDURE

Brainstorm the elements and compounds that you encounter in their pure form in your everyday life.

List as many elements and compounds as possible and indicate the uses of each.

Each group will write its list on the board.

Elements Functions/Uses

Compounds Functions/Uses



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Lesson 8

INDUSTRIAL ELEMENTS AND COMPOUNDS TIME



OBJECTIVES


identify elements and compounds used by business/industries;

analyze the importance of elements and compounds which are vital to the national economy.

PREREQUISITE

1. The students should have prior knowledge on the existence of elements and compounds in their daily lives.

2. Group report on the composition of some common products.

RESOURCES

Table of elements and compounds in industries.

Concept strips PROCEDURE

Opening Activity

Discuss the role of elements and compounds in an industrial setting.



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Living in today’s technological society sometimes produces a strange blind spot. People think that the items needed in life naturally pop out of the shelves of stores. This thinking is very understandable but many things are no longer produced in the city.

More factories are being situated far away from the urban areas. One effect of this new tendency is that fewer and fewer people get to see for themselves how things are made.

Everything that can be found in stores start out as a natural resource, like coal or trees. Industry is the whole system of processes that turn these natural resources into products.

Main Activity MATCHING STRIPS

a. Explain the instructions on how to do the group activity.

b. Present the materials to be used, such as a table of elements and compounds used in industries, and concept strips.

c. Give each group concept strips of elements and compounds, and strips with functions.

d. Ask the members of each group to match the strips of elements and/or compounds with their functions, and to paste these strips on Manila paper, ready for the group presentation.

Guide Questions

a. What are the different elements and compounds used in industries that are vital to the national economy?

b. Why are these elements and compounds of great help to our economy?

Key Learning Points Some of the important elements and compounds used by business and industry are as follows:

Aluminum. It is a non-toxic metal ideal for the making of cooking

utensils. It is also used in aircrafts, ships and welding irons.

Oxygen is used in welding torches.



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Hydrogen is often used to extract and purify metals like copper,

tin, lead, zinc and iron.

Nitrogen is used to make ammonia, nitric acid and other

nitrogen compounds.

Carbon is widely used in industry as a purifier.

Iron is used in the manufacture of metal products like galvanized iron sheets, window frames, etc.

Silver, because of its beauty, is used for ornaments.

Lead is used in the manufacture of vehicle bearings.

Mercury is used as thermometer liquid.

Gold is extensively used for luxury goods and items.

Aluminum hydroxide is used in mordant dyeing.

Calcium oxide is used in the manufacture of glass.

Calcium carbonate, which makes up chalk, limestone and

marble is used to make quicklime. It is an ingredient of some

toothpaste.

Sodium hydroxide is a major raw material in soap making.

Ammonia is used to make fertilizer.

Closing Statement

Chemical fertilizers such as phosphates and nitrates are widely used in

modern agriculture to produce sufficient harvest for the increasing

population. But their side effects have been very alarming. When too

much chemical fertilizer is applied to the soil, it is usually washed out

into the ground waters, streams, lakes and seas. Nitrates in drinking

water can directly poison human beings. Thus, there is a need to shift

to organic fertilizers as soon as possible.



101



102

ASSESSMENT

Evaluate the group presentation based on the rubrics below:

HOMEWORK

Research on how film negatives and printing papers for pictures are prepared.

Name the different ways of separating mixtures.

REFERENCES

Batobalani for Science and Technology. Chemistry, 9–11.

Department of Education Region IV – A CALABARZON. Chemistry. 55–56.

Fidelino, Mapa, Rabago. Science and Technology III. 46–47.


5 points

Exceptionally well done; accurate and detailed information on the set-up and proper matching of the names and functions of elements and compound. Active participation of the members of each group is observed.

4 points

Accurate and detailed information on the set-up and proper matching of the names and functions of elements and compounds. Members of the group participated in the discussion.

3 points

Accurate information. Some of the names and functions of elements and compounds are not properly matched. Members of the group participated in the discussion.

2 points

Not so accurate information. Some of the names and functions of elements and compounds are not properly matched. Not all members participated in the discussion.

1 point

Incomplete information. Names and functions of elements and compounds are not properly matched. Some members of the group did not participate in the group work.



103

Lesson 9

METHODS OF SEPARATING MIXTURES TIME

Three sessions SETTING

Classroom/laboratory Objectives


identify different methods of separating the components of a mixture;

demonstrate the methods in separating the components of a mixture.

PREREQUISITE

Students should have prior knowledge on basic elements and compounds encountered in daily life.

RESOURCES

salt, water, sand, oil, iron fillings, sea water, filter paper, evaporating dish, beaker, funnel, test tube, test tube rack, alcohol lamp, distilling tube

illustrations of different separation techniques PROCEDURE

Opening Activity

Begin the session with the definition of mixtures. Ask the students to list down examples of mixtures. Discuss the components present in each of the mixtures cited in the examples. Ask the students how they think these mixtures are separated and what instruments can be used in doing so.



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Mixtures abound in the environment. Most mixtures, however,

cannot be used in their natural form. These mixtures have to be separated into useful components.

The purification of the components is necessary in most instances. Separation and purification methods used are determined by the properties of the mixture itself and of the components to be recovered.

In today’s lesson you will learn about the common methods used in separating mixtures into their components and in purifying the components sought for. You may have previously performed some of these methods at home.

Main Activity EVALUATING AND SEPARATING MIXTURES

1. Divide the class into five groups and ask each group to select a leader.

2. Assign a mixture to each of the different groups.

GROUP MIXTURE

1 Iron fillings and sand (use a magnet)

2 Table salt and water (evaporation)

3 Sand and water (filtration)

4 Oil and water (decantation)

5 Seawater (distillation)

3. Ask the students to evaluate the mixture assigned to their group and to determine its components. Tell them to discuss how these components can be separated.

4. On the blackboard, post the illustrations on the different methods of separating liquids.

5. Inform the students that they are to choose from among the six illustrations on the blackboard the method that can be used to separate the mixture assigned to them.

6. Require the groups to present and explain the procedure they chose to the class.



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Guide Questions

1. What is a mixture?

2. How are mixtures separated?

3. What methods are used to separate mixtures?

4. Which method do you think is most commonly used at home? Key Learning Points

Show the illustrations of the different separation methods to the class and discuss each. The common methods in separating mixtures include the following:

a. Filtration. This method uses filter

paper or fine porous ceramic to

separate a solid from a liquid. It

works because while the

dissolved particles are too small

to be filtered, non-dissolved solid

particles are too big to go through

the filter paper.

b. Decantation. In this method, the

insoluble solid that settles at the

bottom of the container is

separated from the liquid by

pouring it out. By pouring the

supernatant liquid into another

container, it is removed from the

insoluble solid.

c. Floatation. This method is used

when some solids of a

suspension settle at the bottom of

a container and the less dense

material is taken off.

Stirring rod

Empty glass



106

d. Evaporation. This method is

applicable when a mixture

consists of a nonvolatile

component dissolved in a

solution. The solvent evaporates,

leaving behind solid residue.

e. Distillation and condensing a liquid. This method is used to recover

and purify components of liquid mixtures with varying boiling points.

f. Several methods of distillation exist:

Simple distillation. This method is used when the impurities of a mixture are not volatile and the sought substance does not decompose at its boiling point.

Fractional distillation. This method is used to effectively separate liquid mixtures with narrow differences in boiling points.

Steam distillation. This method is used when the sought substance is steam volatile or vaporized with the steam. The unwanted non-volatile fraction is left behind.

Delivery tube

Test tube

Receiver seawater

Beaker with water

Distillation Condensation

thermometer

cold water out

liebig condenser

solution

anti-bumping granules

HEAT distillate

cold water in



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Closing Statement

Besides those discussed in this lesson, other methods in separating mixtures exist. You will learn them as you progress in your study of chemistry. The other methods are used for more complex mixtures, such as animal and plant pigments.

Purifying water is a simple separation and purification method used in our homes. There are times however when one separation method is not sufficient, making it necessary for the different methods to be used so as to recover the substance in pure form.

ASSESSMENT

a. Describe the method used in separating or recovering the substance given:

1. sand and water (Ans: filtration using a wire mesh)

2. coconut oil from coconut gata (Ans: evaporation of the water from the gata)

3. crude oil (Ans: fractional distillation)

4. sand and salt (Ans: filtration and evaporation)

5. essential oil in orange (Ans: filtration and evaporation)

b. Explain why filtration is faster when a fluted filter paper is used rather than an ordinary, folded filter paper.

(Ans: The filter paper with flutes has more filtering area than ordinary filter paper, which is folded in quadrants.)

HOMEWORK

Garbage is a good example of a mixture consisting of various waste materials. Ask the students to design a practical way of separating the different components of garbage.

REFERENCES

Magno, Tan, Punzalan. Science and Technology for a Better Life, 43–

52.


Rabago Mapa, Fidelino. Science and Technology III. 53–55.



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Lesson 10

MIXTURE PREPARATION AND RECOVERY

TIME

Three sessions

SETTING


OBJECTIVES


prepare useful mixtures from available resources in the community;

recover useful chemicals from natural mixtures. PREREQUISITE

a. The students should have prior knowledge on the different methods of separating mixtures.

b. Students should be prepared to present their work to the teacher for checking.

RESOURCES

various kitchen chemicals and fruits

salt, pepper, sugar, vinegar, cooking oil, soy sauce, calamansi juice, coffee, camote, cubes, banana, apple, jackfruit, coconut milk, raisins, gelatin, milk

mixing bowls, aluminum pan, alcohol burner

tripod or substitute metal stand



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PROCEDURE Opening Statement

We prepare different kinds of mixtures everyday. An all-time favorite is fruit salad. Can you cite the ingredients that we use to prepare this very delicious dessert? In most cases, fruit salad includes grapes, cherries, pineapple, peaches, banana, all-purpose cream and milk. Almost all foods can be considered as mixtures, along with herbal medicine and hand and body lotion. Our lesson for today has something to do with the useful mixtures that we encounter everyday.

Main Activity PREPARATION OF USEFUL MIXTURES

a. Put salt, pepper, sugar, vinegar and cooking oil in a bottle. Then add water to the mixture. Cover the bottle and shake it vigorously, Turn it upside down and then put the bottle right side up on the table. Observe what happens.

b. Ask the students:

Which particle settled first? Second? Third? Last?

What do you call the settling of particles in liquid?

What are the different methods of separating mixtures?

c. Introduce the next activity, the objectives and the procedures to be followed by each group.

d. Give each group the materials to be used, such as the table of elements and compounds used in industries and concept strips of elements and compounds, and strips with functions.

e. Allow students to prepare as many mixtures as they can, using the given materials. They have to match the strips of elements and/or compounds with their functions. They will note down all the materials that were used in the mixtures.

f. Ask each group to paste these strips on manila paper, ready for the group presentation.



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Key Learning Points

A. There are various kinds of mixtures

Calamansi juice and soy sauce (dip)

Instant coffee, sugar and water (coffee)

Calamansi juice, sugar and water (juice)

Vinegar, salt, pepper (to season the meat)

Coconut milk, banana, sugar, jackfruit (ginataan)

Vinegar, cooking oil, spices (salad dressing)

Gelatin, water, sugar, milk, raisin (gulaman)

B. Mixtures can be formed by stirring, mixing and shaking.

C. Mixtures can be identified based on the following properties: texture, phase, color and state.

Closing Statement

Ask students to give examples of products from industries, which are produced and/ or recovered from mixtures.

The abaca plant is a natural mixture. Its fibers are made into

handicrafts, a kind of woven cloth called “sinamay”, and ropes

more popularly known as Manila hemp.

Although the leaves and stalks of other plants, like ramie, “buri”

and “saluyot” are also rich in cellulose fibers, their fibers have to

be separated or extracted from the plants before they can be

used as fabric/bags/hats (ramie fiber) and hat/mats/bags (“buri”

fiber).

Piňa cloth, which is used for making “Barong Tagalog” is made

from the fibers of pineapple leaves.



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ASSESSMENT

Evaluate the group performance based on the rubric below:

5 points Ability to follow procedures carefully, active participation and the unity of the members are observed.

4 points Ability to follow procedure. Active participation of the members is observed.

3 points Ability to follow procedure. Some of the members are active, others are not.

2 points Inability to follow procedures carefully; observed that only some members are united

1 point Inability to follow the procedure. Members are inactive and have no unity at all.

HOMEWORK

Discarded materials like spent dry cells may be recycled into useful chemicals. Zinc metal, carbon rod, manganese dioxide and ammonium chloride can be recovered from a spent dry cell.

Conduct a research on how to separate the components of a discarded dry cell. Think of it as an exercise in recycling waste materials. Do it as a group project.

Study and prepare for the first periodical examination.

REFERENCES

Amurao, Callope, Serrano, Villaverde. Laboratory Manual for Science Chemistry. 50–54.

Bon, Milagros. Science and Technology Chemistry PSSLC. 31–39.




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Student Activity 10

PREPARATION OF USEFUL MIXTURES

OBJECTIVE

In this activity, your team will prepare useful mixtures from available resources in the community.

RESOURCES

salt calamansi juice coconut milk

pepper coffee raisin

sugar camote cubes gelatin

vinegar banana milk

soy sauce apple

cooking oil jackfruit

mixing bowls alcohol burner

aluminum pan tripod or substitute metal stand PROCEDURE

1. Let the students form groups of eight.

2. Prepare as many mixtures as you can using the materials in the list.

3. Note down all the materials that were used in the mixtures listed in the table below.

4. Discuss the different mixtures in class.

Mixture No. Ingredients/Materials used End Product

Mixture 1

Mixture 2

Mixture 3

Mixture 4

Mixture 5

GUIDE QUESTIONS

1. How did you form the mixtures?

2. What properties did the mixtures have?

3. How did they differ from each other?

4. How can material mixtures be made useful?

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