Kwun Tong Government Secondary School

KWUN TONG GOVERNMENT SECONDARY SCHOOL

Yearly Examination 2003-2004

Integrated Science

Class : S.2 ( ) Max. Mark : 100

Name : ______Date : 24-6-2004

Class No.: ______Time : 8:45-9:45am

Answer all of the questions on the answer sheet provided

(A) Multiple Choice (20 marks)

1. Which of the following can be used to test for starch?

A. Hydrogencarbonate indicator B. Lime water

C. Dry cobalt chloride paper D. Iodine solution

2. What is the energy change in photosynthesis?

A. Light energy to heat energy B. Light energy to chemical energy

C. Chemical energy to heat energy D. Chemical energy to kinetic energy

3. The best way to prevent lung cancer is

A. to reduce tar content in the cigarette. B. to add a filter to the cigarette.

C. not to smoke at all. D. to smoke fewer cigarettes a day.

4. A fire extinguisher containing carbon dioxide puts out fire by

A. removing the fuel. B. lowering the temperature.

C. cutting down the supply of oxygen. D. mixing with the fuel.

5. The presence of carbon dioxide can be shown with

(I) a piece of dry cobalt chloride paper. (II) lime water.

(III) a glowing splint. (IV) hydrogencarbonate indicator.

A. (I) and (III) only B. (II) and (III) only C. (I) and (IV) only D. (II) and (IV) only

6. Which of the following materials is an insulator of electricity?

A. Plastic B. Copper C. Iron D. Gold

7. What is the use of the earth wire in an electrical appliance?

A. To direct current to earth when we switch on the appliance

B. To protect us from an electric shock

C. To supply electricity to the electrical appliance

D. To reduce the current loading by sharing the current with the neutral wire

8. Light bulbs X and Y are identical. How much current passes through the light bulbs?

Bulb X Bulb Y Bulb X Bulb Y

A. 0.1 A 0.1 A B. 0.05 A 0.1 A

C. 0.1 A 0.05 A D. 0.05 A 0.05 A

9. Which of the following devices make use of the heating effect of current?

(I) Toaster (II) Heater (III) Fan (IV) Radio

A. (I) and (II) only B. (I) and (III) only C. (II) and (III) only D. (II) and (IV) only

10. Which of the following is a safety device that can cut off the electricity when the

current is too large?

A. Ammeter B. Circuit breaker C. Rheostat D. Voltmeter

11. Study the ammeter readings below. How much current does the wire carry?

Given 1 A = 1000 mA

A. 76 mA B. 73 mA C. 78 mA D. 80 mA

12. Which of the following is/are the effect(s) of contact force?

(I) Rain drops from the sky.

(II) A magnet attracts iron paper clips.

(III) A baseball is hit by a club.

A. (I) only B. (III) only C. (I) and (II) only D. (II) and (III) only

13. A ball rolling on the ground will finally stop. What is the reason?

A. There is no force to push it continuously.

B. The ball uses up its potential energy.

C. Friction between the ball and the ground surface opposes its motion.

D. The force of reaction is greater than the force of action.

14. Which of the following is/are (a) food preservative(s)?

(I) Benzoic acid (II) Distilled water (III) Sodium hydroxide

A. (I) only B. (I) and (III) only C. (II) and (III) only D. All of them

15. Which of the following pairs of chemicals reacts and forms sodium chloride?

A. Sulphuric acid and copper sulphate

B. Copper sulphate and sodium hydroxide

C. Hydrochloric acid and copper sulphate

D. Hydrochloric acid and sodium hydroxide

16. Which of the following liquids has the highest pH value?

A. Ammonia B. Distilled water C. Sodium hydroxide D. Saliva

17. A person with short sight

A. cannot see near objects clearly. B. cannot see clearly in dim light.

C. cannot see distant objects clearly. D. cannot distinguish between colours.

18. Which of the following parts of the body can detect the flavour of food?

(I) Tongue (II) Nose (III) Brain

A. (I) only B. (II) only C. (III) only D. (I) and (II) only

19. The following diagram shows the pupil of an eye in dim light. How does the pupil change when the light becomes brighter?

20. A person first looks at a distant object and then reads a book. What is the change of the thickness of his lens during this process?

(B) True or False Statements (10 marks)

Write 'T' for a true statement and 'F' for a false one.

1. Breathed air and unbreathed air contain the same amount of nitrogen.

2. All green plants are producers.

3. In a series circuit, the voltage is the same at every point.

4. A fuse can protect electrical appliances from damage by a large current, as well as our lives.

5. The colour of the live wire is red and green.

6. On a rainy day, cars have slippery tyres easily because water on the road surface reduces friction.

7. Litmus solutions are useful indicators for testing the pH values of liquids.

8. Acidic wastes in the laboratory should be neutralized by water before they are disposed.

9. Sound is produced by vibrations. Therefore, it can travel in space.

10. Drug abuse means taking drugs according to doctor's instructions.

(C) Matching (10 marks)

Column A / Column B
1. chlorophyll / A. when the switch is ‘ON’
2. oxygen / B. when the switch is ‘OFF’
3. electric circuit / C. absorbs light to carry out photosynthesis
4. plug in an electrical appliance / D. neutralized by vinegar
5. lubricant / E. increase friction
6. mosquito stings / F. neutralized by baking soda
7. ammonia solution / G. relights glowing splint
8. cornea / H. turn dry cobalt chloride paper pink
9. drug abuse / I. reduces friction
10. reaction time / J. a complete route through which electric current can flow
K. time taken to react to a stimulus
L. transparent part of eye
M. damages the brain
N. weak alkali

(D) Fill in the blanks (20 marks)

1. A voltmeter is connected in (a) to measure the (b) applied to a component in a circuit.

2. Every fuse has a number printed on it. If the current exceeds this number, the fuse (c)____ out. The number is called the fuse (d) .

3. A magnet can pull iron nails towards it without touching them. The force of the magnet is a (e) force.

4. The pulling of gravity on an object is the (f) of the object.

5. All objects on the Earth are pulled towards the ground by the force of (g)_____ .

6. If a force is continuously acting on a moving object, the speed of the object will (h)______.

7. The force which exists between two surfaces and always opposes the motion of a body is (i) .

8. A (j) is used to measure the strength of a force.

9. When litmus solution is added to vinegar, it turns (k) .

10. Chemical with pH value 7 is said to be (l) .

11. We should wear safety goggles and gloves when handling acids and alkalis. It is because they are very (m) ___ .

12. (n) is a medicine that can neutralize excess acid in our stomach.

13. Chemicals in food dissolve in the saliva and stimulate the (o) to give the sense of taste.

14. The five human senses are hearing, smell, (p) , (q) and
(r) .

15. Messages from sense organs are carried through (s) ______to the

(t) ______which is the control centre of our body.

(E) Short Questions (40 marks)

1. (a) Study the circuit below and complete the following table. (4 marks)

Use ‘0’ to indicate that the bulb is out

and ‘1’ to indicate that the bulb lights up.

(b) If more bulbs are added to a series circuit, what happens to the bulbs? (3 marks)

[Total : 7 marks]

2. A spring can be stretched by a force. A smaller force can produce a smaller stretch whereas a larger force can produce a larger stretch. Thus the amount of stretch can tell us the strength of a force being used. An experiment was done to investigate how the amount of stretch of a given spring changes with the strength of the force. The graph below shows the result obtained from the experiment.

(a) What force would produce the following stretch?

(i) 4 cm (1 mark)

(ii) 7 cm (1 mark)

(b) What stretch would these forces produce?

(i) 3 N (1 mark)

(ii) 5.5 N (1 mark)

(c) Explain briefly why we cannot predict the stretch produced by a 50 N force from the information in the graph? (1 mark)

(d) If we use a stiff (堅硬) spring to repeat the experiment, would the line obtained be steeper(更陡峭)? Sketch it on the graph (2 marks).

[Total : 7 marks]

3. In the following diagram, a colourless soft drink contained in a test-tube is heated. The gas released passes through some lime water.

(a) Suggest an indicator that can show the pH value of the soft drink. (2 marks)

(b) Is the soft drink a weak acid or a strong acid? (1 mark)

(d) After the gas released from the soft drink passes through the lime water, what will happen to the lime water? (2 marks)

(e) Suggest another indicator that can be used to replace lime water in the experiment. How does the indicator change in the presence of the gas? (3 marks)

[Total : 10 marks]

4. The following diagram shows the structure of the eye.

(a) Give the name and the colour of layer A. What is the function of it? (3 marks)

(b) Explain why an image falling on C cannot be detected. (1 mark)

(d) Which eye defect does the diagram show? How do you know? (2 marks)

(e) How can this defect be corrected? (1 mark)

(f) Draw a diagram to show how this defeat can be corrected. (3 marks)

[Total : 12 marks]

5. An experiment is performed to find out which part of the body is most sensitive to touch. Student A touches student B on different parts of his body with two needles. At the beginning, two needles have a large separation. The separation is reduced until the touch gives a feeling as if only one needle touches the skin. This separation is then measured and recorded in the following table.

Parts of the body / Minimum separation giving a feeling of touch by one needle (mm)
Forearm / 12
Back / 18
Finger tip / 2
Foot / 23
Palm / 6

(a) Which part of the body is most sensitive to touch? (1 mark)

(b) When the skin is touched by the needles, three kinds of receptors are stimulated. Name ANY two of them. (2 marks)

[Total : 4 marks]

END OF PAPER

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