topic 3 electrolysis and topic 4 oxidation and reduction.pdf

8/13/2019 TOPIC 3 ELECTROLYSIS AND TOPIC 4 OXIDATION AND REDUCTION.pdf

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TOPIC3 : MATERIAL WORLD

TOPIC 4: OXIDATION AND REDUCTION

Readings

Rose Marie Gallgher (1997). Complete Chemistry, Oxford Universiti Press, UK.

Ralph A. Burns (2003). Fundamentals of Chemistry, Prentice Hall, Ney Jersey

Bryan Milner, Jean Martin, John Mills (2002). Core Chemistry, Cambridge Universiti Press

J. G. R. Briggs (2003). Chemistry Insight, Pearson Education Asia Pte. Ltd. Singapore

J.G. R. Briggs (2003). Science in Focus Chemistryfor GCE O Level, Pearson Education Asia

Pte.Ltd. Singapore.

Bahagian Pendidikan Guru, KementerianPendidikan Malaysia. (1995) BukuSumber Pengajaran

Pembelajaran Sains Sekolah Rendah, Jilid 3:Strategi Pengajaran dan Pembelajaran Sains.

Projek PIER Bahagian Pendidikan Guru serta dan Bahagian Perancangan dan

Penyelidikan Dasar Pendidikan, Kuala Lumpur.

Whitten, K.W., Davis, R.E.,Peck,M.L and Stanley, GG. (2008). Chemistry (Ninth Edition).2010

Brooks/Cole.

Keywords

- oxidation- reduction- oxygen- ozone- nonmetal oxides- metal oxides

Learning Outcomes

At the end of this Topic, the learner will be able to;

1. Define oxidation and reduction.2. Explain the meaning of redox and giving examples.

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3. Demonstrate the ability to write balanced formula and the ability to identify oxidizing

agents and reducing from given oxidation-reduction reactions.

4. Ability to differentiate oxygen and ozone.

5. Demonstrate the ability to compare and contrite the properties of oxygen and

hydrogen.

6. Describing with examples the reactions Group 1A and Group 2A with oxygen.

7. Describing what happens to the oxides of Group 1A and Group 2A when it dissolve in

water.

8. Ability to summarize the reactions of O2 with nonmetals ,reactions of nonmetal oxides

with water and the reactions of metal oxides with nonmetal oxides.

Study Questions

Task 1 : Read the definition of oxidation and reduction on Page 225 (highlighted in yellow). Inyour own words, describe oxidation and reduction.

Task 2 : It is said that oxidation and reduction occur simultaneously and are referred to asoxidation-reduction reactions or redox. Read 6-5 Oxidation-Reduction Reactions :Introduction (pg 225). In your own words explain what redox mean and give examplesin your explanation.

Task 3 : Read Example 6-4 Redox Reactions. After going through and understanding the

section, do the following

(a) write balanced formula unit equations for the following redox reactions:

(i) nitrogen reacts with hydrogen to form ammonia

(ii) aluminum reacts with sulfuric acid to produce aluminum sulfate and hydrogen

(iii) zinc sulfide reacts with oxygen to form zinc oxide and sulfur dioxide

(iv) carbon reacts with nitric acid to produce nitrogen dioxide, carbon dioxide andwater

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(b) identify the oxidizing agents and reducing agents in the above oxidation-reduction reactions.

Task 4 : Read 5-9 Oxygen and the oxides (pg 198).Can you differentiate between oxygen and

ozone?

Task 5 : Read 5-8 Hydrogen and hydrides (pg 194) and 5-9 Oxygen and oxides (pg 198). In

your own words, compare and contrast the properties of oxygen with those of

hydrogen.

Task 6 : Read Reactions of O2 with metals on page 198-199. Describe in your own words and

with examples, what happens when Group 1A and Group 2A react with oxygen.

Task 7 : Refer to Page 200, Reactions of Metal Oxides with water. Describe what happens to

the oxides of Group 1A and Group 2A when it dissolve in water.

Task 8 : With reference to page 201-203, write a summary of the following reactions:

(v) Reactions of O2 with nonmetals

(vi) Reactions of nonmetal oxides with water

(vii) Reactions of metal oxides with nonmetal oxides.

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INTRODUCTION

This topic is to teach students about food. As an introduction, you should explain the

importance of food to us.Food is very important to all living beings: humans, animals

and plants. They need food for energy. The energy will be used for growth, development,

repair damaged cells and tissues, reproduction, and maintain general health. In humans

and animals, energy is also used for movement and activity for their everyday life. For

instance, the body cells that are destroyed need to be repaired.

The process of which living organisms obtains food for growing and repairing body cells

is called nutrition. Nutrition is obtained from food. Food provide nutrients. Nutrients

are chemical substances needed in order for us to live and stay healthy. Hence, the energy

is obtained from nutrition in foods utilised to carry out our everyday activities.

TTooppiicc

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Material

World III

By the end of this topic, you should be able to:

1. Explain to students the classes of food and its importance;

2. Conduct a suitable experiment to identify the area of the tongue for different

tastes;

3. Debate about rusty objects; and

4. Conduct suitable experiment to determine the conditions for iron to become

rusty.

LEARNING

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TOPIC 3 MATERIAL WORLD III34

CHEMICAL PROPERTIES OF MATERIALS

3.1.1 Classes of Food

To teach the classes of food, you can use the explanation strategy. Firstly, the teacher

should explain the seven classes of food. The basic nutrients we get from foods are

categorised into seven major classes or categories based on their properties. They are:

Carbohydrates

Proteins

Fats

Vitamins

Minerals

Fibres

Water

Then the teacher can continue the explanation with the functions for every classes of

food.Human and animal bodies need all types of foods to carry out different functions.

The correct proportions of food we consume contain all sources of food. This is called

diet. Diet is the kinds of food we consume and drink regularly.

As mentioned earlier, good diet means we eat food and water at the correct proportions. A

balanced diet should contain about 60% carbohydrates, 20% proteins and 20% fats

coming from food groups. The food will supply nutrients, energy necessary to sustain the

body, for growth and repair and maintain health. The functions of these food are:

(a) Carbohydrates are to supply energy.

(b) Proteins are to provide materials for body growth and repair.

(c) Fats are to supply energy and store excess food.

ACTIVITY 3.1

Testing for the presence of carbohydrate.

The presence of carbohydrate in our food can be tested in the lab. Using tapioca

flour, potato, rice, bread and other samples of food requested by the science

teacher, students may conduct the experiment using iodine solution. Divide your

classroom into several groups for this experiment. Discuss your results.

3.1

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TOPIC 3 MATERIAL WORLD III 35

(d) Vitamins are to provide maintenance and healthy body.

(e) Mineral salts are for healthy teeth, bones, muscles and other parts of the body.

(f) Fibres are to help intestines to function properly.

(g) Water is to process all chemicals in the body and transport substances in the blood.

Lastly, you should explain the importance of the right proportion of the food consumed

everyday. We should eat the right types and amount of food daily to get all the energy

needed. This is called a balanced diet. In order to do this, the relative amounts of different

kinds of food eaten by a person has to be considered. The type of foods consumed can be

illustrated in the form of a Food Pyramid as shown in Figure 3.1.

Figure 3.1:Food Pyramid

Source: www.lifeclinic.com/foods/nutrition/foodpyramid.asp

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3.1.2 Taste of Foods

To teach this lesson, you can use the experiment strategy. Before we do the experiment,

the teacher should explain about the taste of foods. We eat all kinds of food. Food have

different tastes. Food can be categorised into different tastes: sweet, sour, bitter and salty.

Other kinds of tastes are the combinations of these four major tastes. The taste of food

can be detected only by a sensory organ in our mouth called the tongue. The tongue is the

sensory organ that has sensitive cells on the surface. These cells are called taste buds

which contain many taste receptors. These receptors detect the different type of tastes of

our foods. However, the taste of foods can only be detected at different areas on thetongue (Figure 3.2)

Figure 3.2:Area of the tongue responding to different tastes

Source: http://library.thinkquest.org/3750/taste/taste.html

After explaining the different areas on the tongue that can detect different tastes, you can

use the following experiment to give your students the experience of different types of

taste.

ACTIVITY 3.2

Balanced diet

Balanced diets provide all essential nutrients in the correct amount and

proportion of food. It should contain all the seven classes of food. Adults,

adolescents and children need diet with different proportion. Divide your

classroom into seven groups to represent each class of food. In your assigned

group, discuss the factors that determine a persons balanced diet. List all

factors and present the findings to the class.

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3.1.3 Acids and Alkalis

Food are grouped based on their tastes. They are sweet, sour, bitter and salty. Foods that

are sour belong to the acidgroup. The word acid is from the Latin word acidus which

means sour. Many sour fruits, especially those which are not ripe, contain acid. All acids

are not of the same strength; some are strong and some are weak. Other food or fruits thatare bitter fall in the alkali group. There are also strong and weak alkalis (see Figure 3.3).

ACTIVITY 3.3

Taste areas of the tongue

This is a lab activity. Work in pairs of two. Blindfold your partner. Pour little

amount of solutions of different tastes: salty (salt solution); sweet (sugar

solution); sour (lime juice); and bitter (coffee). Ask your partner to rinse his

tongue with distilled water. Using a straw, place a drop of salt solution onto the

tip of his tongue. Ask him to identify the taste without pulling his/her tongue.

Record your results using a table whether your partner is right (/) or wrong (x).

Repeat the steps on four other areas (tastes) of his tongue but make sure that herinses the tongue using the distilled water before each solution is repeated.

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Figure 3.3:Acidic and alkaline foods and fruits

Source:http://buywaterfilter.my

Using a specific procedure in the lab, you can use a litmus or pH paper to test the

presence of acid or alkali in the substances you select. Most of the time, materials

containing acid will turn the blue litmus or pH paper to red colour. On the other hand,

alkali will turn the red litmus or pH paper to blue. (Figure 3.4). Can you list at least two

substances in your everyday life in both groups of acid and alkali?

Figure 3.4:pH scale ranges from 1 to 14 to indicate the strength of an acid or alkali

Source:dtc.prima.edu/~biology/.../lesson2d.htm

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3.1.4 Household Products

You can also explain further the use of acid and alkali for cleaning purposes. Different

objects in the house will require different types of cleaning products; hence, we need to

use the products that have specific functions. The household products can be categorised

into two groups: acidic or alkaline. Most of the household products like alkaline are

sodium hydroxide (for making soap and detergent); ammonia (household cleaner,drainage opener, sink opener), lime (to raise the pH value of acidic soil for healthy

growth of plants); magnesium hydroxide (used in antacid to ease stomachache due to

excessive acid); toothpaste; baking soda solution; bleach; and many more.

The other group of household products like nitric acid (to make fertiliser and dye); citric

acid and tartaric acid (to make fruit salt); acetic acid (to make synthetic fibre); boric acid

(an eyewash); benzoic acid (to preserve food); carbonic acid (in carbonated drinks);

lemon juice (for drinks); vinegar; and sulfuric acid (liquid from car battery); are some

example of uses of acids. I believe, you can find and name more of the household

products surrounding you from the departmental store during your shopping, as compared

to browsing through the Internet! Then you can use this example to explain or discusswith your students.

ACTIVITY 3.4

Identification of substances: acidic or alkaline

You can ask your students to bring anything from home like fruit (lemon, lime,

mango, guava, papaya, banana, etc.) carbonated drink, toothpaste, detergent,

soap, shampoo, hair conditioner, milk, vinegar, distilled water or others by your

science teacher. In the laboratory, you will be conducting an experiment to

identify those substances whether they are acid or alkali. Use the litmus or pH

paper to indicate the presence of acid and alkali.

Source: dtc.prima.edu/~biology/.../lesson2d.htm

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RUSTING

3.2.1 Investigate Material that can Rust Up

Start this lesson by asking student these questions; when you walk at the children

playground, can you trace which objects can become rusty and which ones cannot? Can

you differentiate the properties of the objects that can rust and which one cannot? (Figure

3.5)

Figure 3.5:Playground

Source:http://boston.about.com/od/walkingtours/ss/bcWalkingTour_6.htm

Objects that are made from iron and steel can become rusty. These objects have a

reddish-brown stuff formed on their surface when rusty. The mass of the objects will

increase when the rust formed on the surface. This process of rust formation is known as

rusting. However, not all objects can become rusty. Objects made from clay, wood, fibre,

3.2

ACTIVITY 3.5

Browse through the Internet. Find out on how to make:

1. Soap (using alkali)

2. Salt (using alkali and acid)

Write your report and present them to the class according to groups.

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plastic and glass are the few examples of non-rusty objects. Find and list more examples

about rusty and non-rusty objects. To make the teaching process more interesting, you

can ask students to do the activity below:

3.2.2 Why do Objects Rust?

Before this, we have learned that objects made of iron and steel can become rusty. For

example, a nail, can become rusty. When you compare a nail in your house and the nail

outside the house, why is the nail outside the house often rusty? Can you explain this

phenomenon? Is it possible for us to infer why that one nail has become rusty, but others

still look gray and shiny? Why do objects like nails rust? To understand this behaviour,

we need to learn some chemical reactions which underlies the process of rusting. Perhaps

you have never heard of oxidation reactions. Yet, this type of reaction has many

important applications in our everyday life. When you see a rusty nail, you are actually

observing a process of oxidation.

Historically, the term oxidation was used for reactions of the elements with oxygen to

form oxides. All metals exhibit a tendency to be oxidised, some more easily than others.

Metals used in building materials, such as iron, eventually oxidise, which causes

deterioration of the metal. Known as corrosion, this process results in rust and other

corrosionon cars, bridges, ships and underground pipes.

ACTIVITY 3.6

Should we replace all rusty objects with non-rusty objects? Form your own

group and make your stand whether you are for or against this motion.

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Figure 3.6:An abandoned rusty car

Source: http://www.nsls.bnl.gov/about/everyday/corrosion.html

3.2.3 Factors Needed for Iron to Rust

Now we know that iron can become rusty through the process of oxidation. What is the

meaning of oxidation? To understand this, we should identify the determining factors

needed for iron to rust. Then ask your students to do the experiment below:

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ACTIVITY 3.7

Experiment 1: Rusting

Students will conduct experiment to determine what conditions are necessary

for iron to change into the iron oxide compound.

Materials:

Test tubes (4)

Stopper

Test tube rack 100ml graduated cylinder

250ml cylinder

Few pieces of nails

Salt

Pencil

Procedure:

1. Students work in groups of four.

2. Students hypothesise which nail will rust.

3. Students will be given data table.

4. Label the test tubes W, X, Y, and Z.

5. Measure 50ml of vegetable oil and pour into a 100ml beaker.

6. Measure 50ml of water and pour into a second 100ml beaker.

7. Measure 50ml of water and pour into third 100ml beaker. Add salt until

no more salt will dissolve.

8. Place one piece of nail into each of the three 100ml beakers. Drop the

fourth nail into the test tube W. Put a stopper on the test tube and placein the test tube rack.

9. Use forceps to remove the nail from the oil and place into the bottom of

test tube X. Place in the rack.

10. Repeat the process for the nail from both water and salt solutions and

place into test tubes Y and Z.

11. Students work in groups of four.

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12. Students hypothesise which nail will rust.

13. Students will be given data table.

14. Label the test tubes W, X, Y, and Z.

15. Measure 50ml of vegetable oil and pour into a 100ml beaker.

16. Measure 50ml of water and pour into a second 100 ml beaker.

17. Measure 50ml of water and pour into third 100ml beaker. Add salt untilno more salt will dissolve.

18. Place one piece of nail into each of the three 100ml beakers. Drop thefourth nail into the test tube W. Put a stopper on the test tube and place

in the test tube rack.

19. Use forceps to remove the nail from the oil and place into the bottom

of test tube X. Place in the rack.

20. Repeat the process for the nail from both water and salt solutions and

place into test tubes Y and Z.

21. Measure 100ml of water into the 250ml beaker. Tape the four test tubes

together and invert them into the beaker and support them.

22. Record your observations in the data table everyday for three days.

Data and observation

Test tube Day one Day two Day three

W The nail still looksgray and shiny

The nail still looksgray and shiny


X The nail still looksgray and shiny



Y A reddish-brown stuffappears on the surface

of the nail

A reddish-brown

stuff appears on thesurface of the nail

A reddish-brown

stuff appears on thesurface of the nail

Z More reddish-brownstuff appears on thesurface of the nailcompared to Y

More reddish-brownstuff appears on thesurface of the nailcompared to Y

More reddish-brownstuff appears on the

surface of the nailcompared to Y

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Here are some tips that you can give to your students when they are doing a science

project or experiment.

Tips

To do science project systematically, you may follow the following steps. First, you

must realise the purpose of doing this science project (Are you testing different

substance that are able to prevent rust from forming? Or, to determine which rustremover was more efficient in removing rust from iron?).

Secondly, you should determine the hypothesis of this experiment. You can create your

hypothesis creatively, but I suggest you to consider substance that you believe to be the

most effective in preventing the act of rust.

Questions:

1. In which test tubes did the nail change into the compound iron oxide?

2. Why didn't the nails rust in the other test tubes?

3. What factor increased the rate of the reaction? Why?

4. What was the purpose of test tube W?

5. What is necessary for the formation of the compound iron oxide?

Answers:

1. In test tubes Y and Z

2. Either oxygen or water was not in contact with the nail. In test tube W,the lack of water prevented the iron from oxidising. In test tube X, the

vegetable oil protected the nail from rusting

3. Salt increased the rate of chemical change. The salt solution cleaned thesurface of the nail

4. Control

5. Iron, oxygen and water

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Thirdly, you should design your experiment in order to test your hypothesis. You

should recognise which variable is constant, how you can manipulate certain variable

and observe or measure the effect of this manipulated variable on certain independent

variable. You may discuss with your friends about the variable which is to be held

constant for this experiment However, it is suggested that different kind of rust

inhibitor as the manipulated variable. Rust inhibitor is defined as a substance to prevent

the act of rust from occurring. Paints are used on cars, bridges and many other items

that are usually exposed to damp air. In car radiators, anti-freeze is used since is has a

high boiling point, allowing the car to run at a high temperature without boiling away

the coolant and contains chemicals that can inhibit waters tendency to rust. Tinplate is

used for manufacturing cans and protects the steel from rusting and corrosion. Waxesare used in manufacturing as rust preventatives. Well, now we have already determined

which element act as manipulated variable. How about the dependent or responding

variable? Can you find any material around your house to be used as the responding

variable? Maybe you can use a nail, since it is cheap and easy to obtain.

After you have collected all the relevant materials, the fourth step you should do is to

conduct the experiment. The rust inhibitors which act as manipulated variable in this

experiment are the paint, the paraffin wax and the car polish. Therefore, we can decide

that there are three experimental groups in this study and one control group. Following

are the detail of each group.

Group Characteristic

Experiment 1 A nail coated with paraffin wax

Experiment 2 A nail coated with paint

Experiment 3 A nail coated with car polish

Control Does not have any rust inhibitor applied on it

Let all the nails dry overnight. After you have let the nails dry, sprinkle them with tap

water on the morning, afternoon and evening. Do this for a week. After a week, can

you discover which nail has a lot of rust and which nail doesnt? After you have the

result, what can you conclude?

At the end of this lesson, you can ask students to make conclusion. What can they

conclude from this experiment? Let us read more to relate with the findings. Three things

are required for iron to turn into iron oxide. These things are water, oxygen and iron

itself. When a drop of water strikes an iron object, two things begin to occur almost

instantaneously. First, the water, a good electrolyte, combines with carbon dioxide in the

air to form a weak carbonic acid, an even better electrolyte. As the acid is formed and the

iron dissolved, some of the water will begin to break down into its component, that is

hydrogen and oxygen. The free oxygen and dissolved iron bond into iron oxide, in the

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process of freeing the electrons. The electrons liberated from the anode portion of the iron

flow to the cathode, which may be a piece of a metal less electrically reactive than iron,

or another point on the piece of iron itself.

The chemical compounds found in liquids like acid rain and seawater, make them better

electrolytes than pure water. This allows their presence to speed up the process of rusting

on iron and other forms of corrosion on other metals. The type of metal also plays a big

role in the rate at which corrosion occurs. For example, chromium corrodes much slower

than iron. Other valuable metals like sterling silver, platinum and gold are hardly

corroded at all. The environment also plays a role in corrosion. Metals corrode faster in

hot humid climates and slower in cold dry ones.

Another way to understand how the process of rusting happens is through several

chemical equations. The process of rusting requires an anode and cathode in different

places on the surface of a piece of iron. In one area of the iron (Fe) surface, called the

anoderegion, the oxidation half reaction takes places.

Anode (oxidation): Fe(s)Fe2+

(aq) + 2e-

or 2Fe(s)2Fe2+

(aq) + 4e-

The electrons move through the iron metal from anode to an area called the cathode

region where oxygen (O2) dissolved in water is reduced to water (H2O).

Cathode (reduction): O2(g) + 4H+(aq) + 4e-2H2O(l)

By combining the half reactions that occur in the anode and cathode regions, we can write

the overall oxidation-reduction process.

2Fe(s) + O2(g) + 4H+(aq)2Fe

2+(aq) + 2H2O(l)

The formation of rust occurs as Fe2+

ions move out of the anode region and come in

contract with dissolved oxygen (O2). The Fe2+

oxidises to give Fe3+

, which reacts with

oxygen to form of rust.

4Fe2+

(aq) + O2(g) + 4H2O(l)2Fe2O3+ 8H+(aq)

We can write the formation of rust starting with solid Fe reacting with O 2 as follows.

There is no H+in the overall equation because H

+is produced in equal quantities.

Corrosion of iron

4Fe(s) + 3O2(g)2Fe2O3

Rust

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3.2.4 Protection Against Rust

Rusty objects look unattractive and old. They become brittle and corrode slowly.

Basically, we can prevent rusting by preventing the iron objects from coming into contact

with air and water. This can be done by coating the objects with non-rusting material like

paint, oil, grease or any non-rusting materials. Iron objects also can be galvanised to

prevent the iron from rusting.

Other than that, we can also remove rust by using electrolysis (see Figure 3.7). In doing

this, you need a plastic bucket, battery charger, baking soda and electrode. It can be done

by providing a flow of electrical current and the rust will move with the electrical current.

To get the current flow, fill your plastic bucket with water. Add about a tablespoon ofbaking soda per gallon to the water. Once the current is started, adding more soda will not

make the process go faster. Put the object into the water with the NEGATIVElead on it.

Now, put in your electrode which could be a nail, screw, or any piece of metal. Stainless

steel works the best. Then, attach the POSITIVE lead to the electrode. Now switch

ONthe battery charger and observe the rust going away.

Figure 3.7:The process of electrolysis

Source:http://www.thepontiactransampage.com/rust.html

3.2.5 The Benefits of Protection against Rust

The problem associated with rusting can be associated with utilities, transportation and

infrastructure. Therefore, it is important to prevent metals around us, especially iron, from

rusting. An old iron object need not be replaced if we can prevent it from rusting.

Therefore, it will save cost. Iron objects which are not rusty look shiny and new

compared to iron objects which have become rusty. Look at Figure 3.8. It shows a

photograph of a badly corroded truck after many years of marine atmospheric exposure.

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Figure 3.8:A badly corroded truck after many years of marine atmospheric exposure

Source: http://www.electrochem.org/dl/interface/spr/spr06/spr06_p24-26.pdf

The teacher also can give students a group work assignment and science project as

activity below so that they can understand better.

ACTIVITY 3.8

There are so many mega structures in Malaysia. Yet, our country has a climate

that is humid and hot. Based on this circumstance, it is possible that rusting is

one of the problems which are faced by us in Malaysia when maintaining those

mega structures. Can you find information to show an example about how to

maintain one of the mega structures in Malaysia which is associated with

rusting? Do some presentation in front of the class to report about your work.

ACTIVITY 3.9

Conduct a science project to investigate the most effective way to protect iron

object against rust. Do some demonstrations to compare several methods which

are used to prevent materials from rusting.

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Food can be categorised into seven classes: carbohydrates, proteins, vitamins, fats,minerals, fibres and water.

Food have different tastes. They are sour, sweet, bitter and salty.

Food are also classified into two groups. They are acid and alkali.

Acid changes the blue litmus paper to red. While, alkali turns the red litmus paper toblue.

Household products are also divided by the characteristics of being acidic andalkaline.

Materials can be divided into rusty and non-rusty objects.

Rusting process is due to the presence of water, oxygen and iron. This process iscalled oxidation.

Rust can be prevented by certain methods like painting, galvanising and electrolysis

of the metals.

There are benefits through the prevention against rust. Some metals can stay longer

and have a good looking appearence because of the prevention from rusting.

Acid

Alkali

Bitter

Corrosion

Iron

Oxidation

Oxygen

Rust

Salty

Sour

Sweet

Water

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Burns, R. A. (1992). Fundamentals of chemistry (2nd ed.). Englewood Cliffs, NJ:

Prentice Hall.

Hazen, R. M. , & Trefil, J. (1997). The physical sciences: an integrated approach. New

York, NY: John Wiley & Son, Inc.

Kotz, J. C., Treichel, P. M. & Weaver, G.C. (2006) Chemistry and chemical reactivity

(6th ed.). Belmont, CA: Thomson Brooks/Cole.

Milner, B., Martin, J., & Mills, J. (2002). Core chemistry. Cambridge: Cambridge

University Press.

Timberlake, K. C. (2005). Basic chemistry. San Francisco, CA: Pearson

Education Co.

Abandoned rusty car (n.d). http://www.nsls.bnl.gov/about/everyday/ corrosion.html

Retrieved July 6, 2007.

Area of tongue (n.d). http://greenfield.fortunecity.com/rattler/46/upali2.htm Retrieved

July 7, 2007.

Badly corroded truck. (n.d). http://www.electrochem.org/dl/interface/spr/

spr06/spr06_p24-26.pdf Retrieved July 6, 2007.

Food Pyramid. (n.d). www.lifeclinic.com/foods/nutrition/foodpyramid.asp Retrieved July7, 2007.

Household products. (n.d). http://images.search.yahoo.com/search/images/

householdproducts Retrieved July 7, 2007.

pH scale. (n.d). dtc.prima.edu/~biology/.../lesson2d.htm Retrieved July 7, 2007

The process of electrolysis (n.d). http://www.thepontiactransampage. com/rust.html

Retrieved July 6, 2007.

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Rao, C. N. R.. Understanding Chemistry.: World Scientific Publishing Co., . p 238http://site.ebrary.com/id/10422534?ppg=238Copyright World Scientific Publishing Co.. . All r ights reserved.May not be reproduced in any form without permission from the publisher,

except fair uses permitted under U.S. or applicable copyright law.

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topic 3 electrolysis and topic 4 oxidation and reduction.pdf

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