Example of diseases/sickness caused by harmful substance. Basic Science and Technology Primary 3.second term scheme of work

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Week: Six

Class: Primary Three

Topic: Substance that contaminate water

Behavioural objectives: At the end of the lesson, pupils should be able to:

1. identify and name some substances that make water unfit for drinking.

2. explains how dead and decaying animals contaminate water

3. explains how contaminate water.

4. discuss how dumping of refuse in rivers contaminate water.

Instructional material/Reference material: Charts showing ways water can be contaminated, Water contaminated with dust, sand particles

Building Background /connection to prior knowledge: pupils are familiar with water contaminant

Content:

How decay plant and animal contaminate water:

When plants and animals die, they settle to the bottom. Under normal conditions this causes the water body to gradually fill with sediment and organic material and it makes it smell and stink because germs and worms are sedimented and settled in it.

 

How leaking pipe and underground water contaminate water:

Leaky pipes can allow contaminants into our drinking water. … The pressure in mains water pipes usually forces water out through leaks, preventing anything else from getting in. But when there is a significant pressure drop in a damaged section of pipe, water surrounding the pipe can be sucked in through the hole. Underground water contamination occurs when man-made products such as gasoline, oil, road salts and chemicals get into the groundwater and cause it to become unsafe and unfit for human use. … For example, pesticides and fertilizers can find their way into groundwater supplies over time.

How human waste contaminate water:

Human excreta,urine and the lack of adequate personal and domestic hygiene have been implicated in the transmission of many infectious diseases including cholera, typhoid, polio. This really leads to contamination of water which called water disease/water borne disease.

How dumping of refuse in the river contaminate water:

Organic waste (e.g., wood wastes) can have chemical and biological impacts on rivers and streams. Among the many impacts are interfering with the establishment of aquatic plants, affecting the reproductive behavior of fish and other animals, and depleting the water of dissolved oxygen as the wastes decompose.

Evaluation: The teacher asked questions on what has been taught.

1. identify and name some substances that make water unfit for drinking.

2. explains how dead and decaying animals contaminate water

3. explains how contaminate water.

4. discuss how dumping of refuse in rivers contaminate water.

Week: Seven

Class:Primary Three

Topic: Water Purification (Making water fit for drinking)

Behavioural objectives: At the end of the lesson, pupils should be able to:

1. explains the meaning of purification of water.

2. describe how distillation process can purify water.

3. explains the meaning and ways of filtration.

4. explains boiling of water a method of purifying water.

5. name and explain how to keep the sources of water clean.

Instructional material/Reference material: Alum Disinfectant e.g. Izal, Dettol, TCP, Miltton solution, Muddy water, Container, Clean white cloth, Stove.

Building Background /connection to prior knowledge: pupils are familiar with Substance that contaminate water.

Content:

Distillation of Water: Distilled water is water that has been boiled into vapor and condensed back into liquid in a separate container. Impurities in the original water that do not boil below or near the boiling point of water remain in the original container. Thus, distilled water is one type of purified water. A water distillation system is designed to purify water cheaply, quickly and effectively. To distill water, all you really need is a heat source .

Water Filtration: Water filtration is a general term that refers to any system or process that is used to filter out particles and pollutants. Water filtration is the process of removing or reducing the concentration of particulate matter,including suspended particles, parasites, bacteria, viruses, and fungi, as well as other undesirable chemical and biological contaminants from contaminated water to produce safe and clean water for a specific purpose.

Boiling of water: Boiling water means that on heating water has reached maximum temperature and temperature of water cannot be raised further or The process of changing the state of a substance from liquid to gas by heating it to its boiling point.

 

Sources of water:

1. Rain

2. Well

3. Tap

4. Spring

5. Lake

6. River

7. Sea

8. Ocean

How to keep the source of water clean

1. Handle and dispose of waste properly:

– Reduce your waste production

-Use local hazardous waste collection programs

– Pick up pet waste

2. Maintain heating oil tanks and fill lines:

– Inspect your oil tank regularly

– Upgrade to a modern fuel tank

– Install a drip pan and oil line/gauge protectors

3. Maintain and use septic systems properly:

– Know the location of your tank and septic beds and protect it from damage

– Have the tank pumped out every three to five years

– Conserve water

Avoid the use of bleach/harsh cleaning products

4. Maintain wells:

– Inspect your well at least once a year

– Keep potential pollutants (i.e. livestock, septic systems, fuel sources, gardens) away from your well

– Test your well water regularly for bacterial contamination

5. Practice water conservation:

– Use a rain barrel to water your garden

– Install low flow shower heads and toilets

– Fix leaking taps

6. Use green products for:

– Household cleaning

– Personal care

– Lawn care

How Distillation process can purify water:

Distillation relies on evaporation to purify water. Contaminated water is heated to form steam. Inorganic compounds and large non-volatile organic molecules do not evaporate with the water and are left behind. The steam then cools and condenses to form purified water.

How to purify water by boiling:

Boil water, if you do not have bottled water. Boiling is sufficient to kill pathogenic bacteria, viruses and protozoa (WHO, 2015). If water is cloudy, let it settle and filter it through a clean cloth, paper boiling water towel, or coffee filter. Bring water to a rolling boil for at least one minute.

Evaluation: The teacher asked questions on what has been taught.

1. explains the meaning of purification of water.

2. describe how distillation process can purify water.

3. explains the meaning and ways of filtration.

4. explains boiling of water a method of purifying water.

5. name and explain how to keep the sources of water clean.

Week: Eight

Class:Primary Three

Topic: Making water fit for drinking (Filtration)

Behavioural objectives:At the end of the lesson, pupils should be

able to:

1. explains and name some chemicals for filtering.

2. describe ways of filtering.

3. explains the changes that occur when alum is put in water.

Instructional material/Reference material:Sieve cloth, Coloured water e.g. muddy water, Basin, Disinfectants e.g. TCP, Dettol, Alum, Charts.

Building Background /connection to prior knowledge: pupils are familiar with water Purification

Content:

Filtration: The act or process of filtering; the mechanical separation of a liquid from the undissolved particles floating in it. Filtration is the process of separating suspended solid matter from a liquid, by causing the latter to pass through the pores of some substance, called a filter. The liquid which has passed through the filter is called the filtrate.

Process of filtration

Filtration. Water flows through a filter designed to remove particles from within it. The filters are made of layers of sand and gravel, and in some cases, crushed anthracite. Filtration collects the suspended impurities in water, enhancing the effectiveness of disinfection.

Evaluation

1. explains and name some chemicals for filtering.

2. describe ways of filtering.

3. explains the changes that occur when alum is put in water.

Week: Nine

Class:Primary Three

Topic: Things about water

Behavioural objectives:At the end of the lesson, pupils should be able to:

1. explains and name things about water

2. explain the process of condensation.

3. explain water as solvent

4. describe the practical work on the water project.

Instructional material/Reference material:Stove, water (boil the water until it evaporates from the kettle), Sun- Water to be kept in an intensive sun heat for evaporation.

Building Background /connection to prior knowledge :pupils are familiar with filtration and it process.

Content:

Water condensation: Condensation is the process by which water vapor in the air is changed into liquid water. Condensation is crucial to the water cycle because it is responsible for the formation of clouds.

Water as a solvent

Water is capable of dissolving a variety of different substances, which is why it is such a good solvent. And, water is called the “universal solvent” because it dissolves more substances than any other liquid. … This allows the water molecule to become attracted to many other different types of molecules.

Evaluation: The teacher asked questions on what has been taught.

1. explains and name things about water

2. explain the process of condensation.

3. explain water as solvent

4. describe the practical work on the water project.

Week: Ten

Class:Primary Three

Topic: More about water purification

Behavioural objectives:At the end of the lesson, pupils should be able to:

1. practicalize

2. practical.

Instructional material/Reference material:Stove, Water, Sieve cloth, TCP

Building Background /connection to prior knowledge: pupils are familiar with water condensation and it process.

Content: WATER PURIFICATION

 

Ways of water purification

BOILING: Boiling is sufficient to kill pathogenic bacteria, viruses and protozoa (WHO, 2015). If water is cloudy, let it settle and filter it through a clean cloth, paperboiling water towel, or coffee filter. Bring water to a rolling boil for at least one minute.

FILTRATION: Filtration is the process of separating suspended solid matter from a liquid, by causing the latter to pass through the pores of some substance, called a filter. The liquid which has passed through the filter is called the filtrate. Water flows through a filter designed to remove particles from within it. The filters are made of layers of sand and gravel, and in some cases, crushed anthracite. Filtration collects the suspended impurities in water, enhancing the effectiveness of disinfection.

ADDITION OF ALUM: Alum (aluminum sulfate) is added to the water to destabilize natural fine particulate matter suspended in water. This process in known as coagulation. … The addition of alum causes these particles and colloids to clump or gather together to form heavier particles which will settle under water.

ADDITION OF DISINFECTANT: Disinfection kills or removes diseases (pathogens) from drinking water, reducing health risks. You can disinfect water by adding chemicals, using heat, using ultraviolet (UV) radiation, filtration, alum, distillation, or using a combination of these methods.

Evaluation: The teacher asked questions on what has been taught.

1. practicalize

2. practical.