SAMPLE EVIDENCE 1

Topic : Effect of impurities on the boiling point of a pure liquidAim To study the effect of impurities on the boiling point of distilled

water

Hypothesis The present of salt increases the boiling point of distilled water

Variables(a) Constant Volume/Amount/Quantity of distilled water(b) Manipulated The Presence of salt (c) Responding Boiling point of distilled water

Material/Apparatus Distilled water, salt, 100 cm3 beaker, wire gauze, tripod stand, Bunsen burner, thermometer

Procedure

1. Distilled water is poured into a beaker until it is half full.2. The water is heated until it boils. The temperature when the water boils (boiling temperature) is recorded3. Two spatulas of salt are added into the distilled water and the mixture is heated again.4. The temperature of the boiling mixture of water and salt is recorded.

Results

The Presence of salt Boiling point of distilled water (oC)

Absent 100

Present 102

Discussion Without impurities the boiling point of distilled water is 100 oC but with the presence of impurities, the boiling point of water is increased. The boiling point of distilled water is increased with the presence of impurities.

Hypothesis is accepted

Conclusion The presence of impurities increases the boiling point of distilled water.

1

Distilled water

Heat

Thermometer

Beaker

C1 P1

C1 P2

C1 P3

Note: All variables must be correct

C1 P4

C1 P5C3 P1

C3 P2

C3 P3

C4 P1

C4 P2

C4 P3

SAMPLE EVIDENCE 2

Topic : Variation

Aim

Hypothesis

Variables Constant : Manipulated : Responding :

Apparatus and Materials:

Procedure :

Result:

Discussion:

Conclusion.

To study the variation of leaves.

Different leaves have different lengths.

Type of plant ( species of plant)Number of leaves Length of leaves

Leaves, ruler

1. 10 leaves from the same plants are collected by the students. 2. The length of a leaf is measured.3. The length of leaves is recorded in the table.4. The experiment is repeated with another leaf.

Number of leaves Length of leaves (cm)1 4.32 5.23 4.14 5.75 5.56 4.47 6.48 6.29 5.3

10 4.5

Variations in the length of the leaves show normal distribution. There is a whole range of intermediates between the shortest and the longest.

Hypothesis is accepted.

Different leaves have different lengths //The length of the leaves show continuous variation

2

Length of leaves /cm

Length of leaf

Metre rule

Leaf

C1 P1

C1 P2

C1 P3

C1 P4

C1 P5

Note: All variables must be correct

C3 P1

C3 P2

C3 P3

C4P1

C4P2

C4P3

SAMPLE EVIDENCE 3

Topic : Exothermic and endothermic reactions

Aim To study exothermic and endothermic reactions.

Hypothesis Different types of chemical cause different changes in temperature in the reaction with water.

Variables(a) Manipulated Types of chemical(b) Responding Increase or decrease in temperature(c) Constant Volume of water / quantity of chemical substances

Material/Apparatus Sodium hydroxide crystals, ammonium chloride powder, distilled water, test tube, thermometer , spatula

Procedure

1. 5cm3 of distilled water is poured into a test tube.2. The initial temperature of distilled water is recorded.3. 1 spatula of sodium hydroxide pellet is added into the test tube.4. The mixture is stirred until the sodium hydroxide dissolved.5. Then the final temperature is recorded in the table.6. The experiment is repeated by using ammonium chloride powder.

3

Thermometer

Distilled water

Ammonium chloridepowder

Sodium hydroxide pellet

C1P1

C1P2

C1P3

Note: All variables must be correct

C1P4

C1P5

ResultsTypes of chemicals

Initial temperature of substance (oC)

Final temperature of substance (oC)

Change in temperature (0C)

Sodium hydroxide crystals and distilled water

29.0 60.0 31.0

Ammonium chloride powder with distilled water.

29.0 15.0

-14.0

Discussion An exothermic reaction occurs when temperature increases because heat is released to the surrounding.An endothermic reaction occurs when temperature decreases because heat is absorbed from the surrounding.

Hypothesis is accepted.

Conclusion 1. An exothermic reaction is a chemical reaction that involves an increase in temperature.

2. An endothermic reaction is a chemical reaction that involves a decrease in temperature.

4

C3P1

C3P2

C3P3

C4P1

C4P2

C4P3

SAMPLE EVIDENCE 4

Topic: Focal length of a convex lens.

Aim

Hypothesis

Variables Constant : Manipulated : Responding :

Apparatus and Materials:

Procedure :

Result:

Discussion:

Conclusion:

To study the focal length of a convex lens.

The thicker the lens, the shorter the focal length.

Type of lens.Thickness of the lensFocal length

Convex lens, lens holder, metre rule, screen.

1. The apparatus is set up as shown in the diagram.2. The lens is directed at a distant object3. The screen is adjusted until a sharp image forms on the

screen.4. The distance between the lens and the screen is measured5. The experiment is repeated using another convex lens with a

different thickness.

Thickness of the lens Focal length(cm)Thin 25

Moderate 20Thick 15

The focal length of a convex lens depends on the thickness of the lens. A thin convex lens has a longer focal length. A thick convex lens has a shorter focal length. Hypothesis is accepted.

The thicker the lens, the shorter the focal length.

5

Rays from distance object

Convex lens screen

C1 P1

C1 P2

Note: All variables must be correct

C3 P1

C4 P3

C4 P2

C4 P1

C3 P3

C1 P5

C1 P4

C1 P3

C3 P2

focal length

SAMPLE EVIDENCE 5

Topic : Resistance of alloy to corrosion.

Aim To investigate the properties of alloy and pure metal

Hypothesis Alloy is more resistance to rust than pure metal.

Variables(a) Manipulated Type of nail(b) Responding Rate of rusting (c) Constant Distilled water, temperature , time

Material/Apparatus Steel nail, pure iron nail, distilled water, test tubes , test tube rack

Procedure

1. Test tubes A and B are prepared.2. 5cm3 of distilled water is poured into test tubes A and B. 3. A steel nail is put into test tube A and an iron nail is put into

test tube B and both test tubes are kept at room temperature for 2 days.

4. After 2 days the condition of the nails are observed and recorded in the table below.

ResultsTypes of nail Presence of rust

Steel nailNo rust

Iron nail Rust

Discussion The steel nail in test tube A is more resistant to rusting than the iron nail in test tube B.Hypothesis is accepted.

Conclusion Steel nail is more resistant to rust than iron nail.

6

Test tube A Test tube B

Distilled water

Steel nail Iron nail

C1 P1

C1 P2

C1 P3

Note: All variables must be correct

C1 P4

C1 P5C3 P1

C3 P2

C3 P3

C4 P1

C4 P2

C4 P3

SAMPLE EVIDENCE 7

Topic: The effect of humidity on the growth of microorganisms

Aim : To study the effect of humidity on the growth of microorganisms

Hypothesis : Microorganisms grow rapidly in moist condition

Variables : Constant : Type of bread/ temperature/ nutrient content Manipulated : Presence of moisture/ water Responding :The growth of microorganisms /mucor/fungi

Materials/Apparatus : 2 pieces of bread, water, clear plastic bag.

Procedure : 1. A piece of bread is sprinkled with water and placed in a clear plastic bag labeled A.

2. The other piece is kept dry and placed in the clear plastic bag labeled B.

3. Both plastic bags are kept in a dark cupboard for two days.4. The result of the experiment is observed and recorded in

the table below.

Results :Presence of moisture The growth of mucorA Moist bread Yes / A lot of mucorB Dry bread No / A few mucor

Data interpretation and discussion

: After two days the mucor grows on the moist bread because of the presence of water but no mucor grows on the dry bread. Mucor needs water to grow. Hypothesis is accepted.

Conclusion : Microorganisms grow rapidly in moist condition

7

B: Dry bread A: Moist bread

Plastic bag

C1 P1

C1 P2

C1 P3Note: All variables must be correct

C1 P4

C1 P5C3 P1

C3 P2

C3 P3

C4 P1

C4 P2

C4 P3

SAMPLE EVIDENCE 8

Topic : The effect of pH on the growth of microorganisms

Aim : To study the relationship between pH value and the growth of microorganisms

Hypothesis : Bacteria thrives in neutral conditions / neutral condition is suitable for the growth of microorganisms

Variables : Constant variable : Volume of nutrient broth Manipulated variable : pH value Responding variable : Cloudiness of the nutrient broth

Materials/ : Sterile nutrient broth, bacteria culture (Bacillus subtilus), distilled water,apparatus hydrochloric acid 1 mol/dm , sodium hydroxide solution 1 mol/dm3 ,

test tubes,cotton wool.

Procedure 1. Three test tubes labeled A,B and C are prepared.2. 5 cm3 of nutrient broth is poured into each test tubes3. 1 cm3 of bacteria culture is added into each test tubes.4. 1cm3 of hydrochloric acid, 1cm3 of sodium hydroxide solution and

1cm3 of distilled water are added by using syringes into the nutrient broth in test tubes A ,B and C respectively.

5. The test tubes A, B and C are plugged with cotton wool6. The three test tubes are kept in the dark cupboard for 2 days.7. The content of the test tubes are observed and recorded.

Observation

Test tubes Condition of the

nutrient agarCloudiness of the

nutrient brothA Acidic Slightly cloudyB Alkaline Slightly cloudyC Neutral Very cloudy

8

Nutrient broth + bacteria culture

A B C Acidic Alkaline Neutral (Hydrochloride acid) ( Sodium hydroxide solution) (Distilled water )

C1 P1

C1 P2

C1 P3

Note: All variables must be correct

C1 P4

C1 P5

C3 P3C3 P2

C3 P1

C3 P3C3 P2

Discussion

After two days , nutrient broth in test tubes A and B becomes only slightly cloudy because microorganisms do not grow well in acidic and alkaline conditions. In test tube C, the nutrient broth becomes very cloudy because microorganisms grow rapidly in neutral condition..

Hypothesis is accepted Conclusion: . Bacteria grows rapidly in neutral condition/ neutral condition is the most suitable pH for the growth of microorganisms.

SAMPLE EVIDENCE 9Topic : PressureAim To study the relationship between weight (force) and depth of

immersion of weight (pressure)

Hypothesis The bigger the mass the deeper the immersion of weight.// The bigger the force the higher the pressure

9

C4 P1

C4 P2

C4 P3

C1 P1

C1 P2

Variables1. manipulated2. responding 3. constant

The mass of weightDepth of immersionSurface area of weight

Materials/Apparatus Flour, 100 g weight, 200 g weight, 300 g weight, retort stand, clamp, container ,metre rule, thread, pair of scissors.

Procedure

1. The apparatus as shown in Diagram 1 is prepared.2. The threat is cut with a pair of scissors and the weight is

let to fall into the flour in the container.3. The depth of immersion of the weight into the flour is

marked on the weight or weight rod as shown in Diagram 2.

4. The depth of immersion is measured and recorded in table below.

10

Diagram 2

depth of immersion

mark

flour

flour

container

thread

40 cm

20 cm

retort stand

Weight100 g

weight rod

Diagram 1

Note: All variables must be correct

C1 P3

C1 P4

5. Steps 1 to 4 are repeated with 200g and 300g weights.

Observation

Mass of weight (g) 100 200 300Depth of immersion (cm) 2 3

4

Discussion The bigger the mass of weight, the bigger the force and pressure produced. A higher pressure causes a deeper immersion.

Hypothesis is accepted.

Conclusion The bigger the force the higher the pressure.

SAMPLE EVIDENCE 10

Topic : Inertia

Aim To investigate the relationship between mass and inertia.

11

C1 P5

C3 P1

C3 P2

C3 P3

C4 P1

C4 P2

C4 P3

C1 P1

Hypothesis The larger the mass of an object ,the greater the inertia of the object.

Variables(a) Manipulated The mass of sphere(b) Responding The distance of the sphere’s movement(c) Constant The angle of inclination , the length of thread,

the mass of pendulum

Material/Apparatus Thread, mass of spheres of 50g, 100g,150g , retort stand , pendulum and metre rule.

Procedure

1. The apparatus is set up as shown in the diagram above. 2. The pendulum with 50g weight is tied to the retort stand with a 50cm length of thread.3. The pendulum is displaced at an angle of inclination of 30º

from the perpendicular and released to knock the 50g sphere on the table.

4. The distance of the sphere’s movement is measured with a metre rule.5. The result is recorded in the table below.6. Steps 1- 5 are repeated by using 100g and 150g mass of sphere.

ResultsMass of sphere/g

Distance of sphere’s movement/cm

50 60

12

30O

ThreadPendulum

Sphere

Retort stand

Table

C1 P2

C1 P3

C1 P4

C1 P5

C3 P1

C3 P2

100 45150 25

Discussion When the mass of the sphere increases the distance of the sphere’s movement decreases. The greater the mass of an object, the greater the inertia.The greater the mass the more the object tends to remain at rest and resist a change in motion.

Hypothesis is accepted.

Conclusion The greater the mass of an object the greater the inertia produced

SAMPLE EVIDENCE 11

Topic : Proprioceptor

Aim : To observe the role of proprioceptors in arrange cans in the correct order without looking

13

C3 P3

C4 P1

C4 P2

C4 P3

C1P1

Hypothesis :. Proprioceptors helps us to arrange cans in the correct order without looking

Variables : manipulated variable : Number of students responding variable : Ability to arrange cans in the correct order fixed variable : Mass of cans

Apparatus : sand, five copper can of equal size

Procedures : 1. This activity must be done in groups 2. All the five cans must be filled with sand of different weights for example:

Can One Two Three Four Five

Weight of sand 50 g 100 g 150 g 200 g 250 g

3. One of my friend is asked to close his eyes4. His eyes are covered with a piece of cloth.5. The five cans are arranged randomly in front of my friend whose eyes

have been covered.6. He is asked to pick up the cans one by one and arrange the cans

according to their weight either in descending and ascending order.7. Role among group members are exchanged and the step above are

repeated.8. The observations are recorded in the table.

ResultNumber of

Student Ability to arrange in the correct order (Yes /No)

1 Yes

2 Yes

3 Yes

4 Yes

5 Yes

Discussion : Proprioceptors are receptor in our body that sense the position of our body that sense the position of our body

14

C1P2

C1P3

C1P4

Note: All variables must be correct

C1P5

C3P1

C3P2

C3P3

We can arrange can without looking because our body has proprioceptorsProprioceptors are important because the enable us to be concious of the position and the posture of our body.The receptor in the muscle related to proprioceptore is called stretch receptor.The other function of proprioceptors also enables us to detect the movement of our body without looking.

Hypothesis is accepted

Conclusion : Proprioceptors are receptor that enable us to be conciousabout the movement of our body parts as well as its functions without using our eyesight

15

C4P1

C4P2

C4P3