KWUN TONG GOVERNMENT SECONDARY SCHOOL
                                  Yearly Examination 2009-2010
                                        Integrated Science
Class    : S.2 (   )                                           Max. Mark                 : 100
Name     : _______________________                             Date                      : 15-6-2010
Class No.: ________                                            Time                      : 8:45-9:45

Answer all of the questions on the answer sheet provided.
(A)  Multiple Choice (20 marks)
1.  Which of the following is a parallel circuit?
     A.                                         B.

      C.                                       D.

2.   The figure below shows a circuit connecting three bulbs.


                                    Q          R

     Which bulbs light up?
     A. P and Q only              B.    P and R only            C.   Q and R only             D.   P, Q and R

3.   Which of the following electric appliances does not make use of heating effect of current?
     A. Electric iron             B. Loudspeaker               C. Electric heater             D.   Hair dryer

4.   Which of the following protect the circuit from overheating by preventing the current from exceeding a
     safety limit?
     (I) Fuse               (II) Circuit breaker                (III) Earth wire
     A. (I) and (II) only   B. (I) and (III) only          C. (II) and (III) only        D. (I), (II) and (III)

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5.   The figure below shows a circuit.

     Assume all the bulbs are identical and the ammeter reading of A1 is 1.5 A, Which of the following is the
     possible readings of ammeters A2 and A3?
         Ammeter A2            Ammeter A3                         Ammeter A2              Ammeter A3
     A.    1A                      2.5 A                               B.   2A                       3.5 A
     C.    3A                      4A                                  D.   3A                       4.5 A

6.   Which of the following is not an advantage of a ring circuit?
     A. It reduces the load in the wires in each path.
     B. Thinner wires can be used.
     C. Electrical appliances can be connected in series.
     D. Current can still flow if one of the paths is damaged.

7.   When we open a can of fizzy soft drink, gas bubbles come out. This gas is
     A. carbon dioxide.          B. nitrogen dioxide.          C. oxygen.                       D.   hydrogen.

8.   After dipping a piece of red litmus paper into lemon juice, the paper will
     A. not change colour.          B. turn blue.           C. turn yellow.                     D.   turn green.

9.   Which of the following can be used to test whether orange juice or lemon juice is more acidic?
     (I) pH paper            (II) Litmus paper             (III) Universal indicator
     A.   (I) only       B.   (I) and (II) only             C.    (I) and (III) only       D.   (II) and (III)

10. Gas bubbles are released when marble chips are put into dilute nitric acid.

                                                  dilute nitric acid

                                                  marble chips

     The gas can
     A. relight a glowing splint.                                 B.   give a ‘pop’ sound with a glowing splint.
     C. give a ‘pop’ sound with a burning splint.                 D.   turn lime water milky.

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11. We should not use acidic cleansing agents to clean marble and limestone surfaces because
    A. the acid can corrode the surfaces.
    B. the marble and limestone absorb the acid and give a bad smell.
      C.   the acid does not react with marble and limestone.
      D.   the acid is explosive.

12. Which of the following is/are weak acid(s)?
    (I) Ethanoic acid in vinegar                       (II) Citric acid in fruits
    (III) Concentrated hydrochloric acid in the laboratory
    A. (I) only         B. (I) and (II) only           C. (I) and (III) only            D.   (I), (II) and (III)

13. Which of the following solutions is the most dangerous?
    A. Dilute ammonia solution                   B. Dilute hydrochloric acid
    C. Concentrated ammonia solution             D. Concentrated hydrochloric acid

14. Acid rain is most commonly found in
    A. deserts.         B. industrial areas.            C.     undeveloped areas.       D.   high-altitude areas.

15. Which of the following products will be formed after mixing an acid with an alkali?
    (I) Salt                (II) Water                    (III) Carbon dioxide
      A.   (I) only      B.   (I) and (II) only         C.     (I) and (III) only       D.   (I), (II) and (III)

16.    Which of the following can be used as a food preservative?
      (I) Citric acid              (II) Distilled water           (III) Sodium hydroxide solution
      A. (I) only         B. (I) and (II) only          C. (I) and (III) only        D. (II) and (III)

17. To living things, a detectable change in the environment is called a
    A. sense.                 B. response.                 C. stimulus.                 D.   sense organ.

Directions: Refer to the sectional diagram of a human eye shown below. Answer questions 18 and 19.



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18.   What happens to structure A when we look at a distant object?
      A.   It becomes smaller.                B.   It becomes thinner.
      C.   It becomes thicker.                D.   It becomes bigger.

19.    Which of the following descriptions about structure B is INCORRECT?
      A. It can produce signals.                        B. It can detect light
      C. It can produce the sense of sight.             D. It contains two kinds of light-sensitive cells.

20. Which of the following is correct about the functions of lenses X and Y?

                              lens X          lens Y

               Lens X                                   Lens Y
      A.   Corrects short sight               Corrects colour blindness
      B.   Corrects long sight                Corrects short sight
      C.   Corrects colour blindness          Corrects long sight
      D.   Corrects short sight               Corrects long sight

(B) True or False Statements (10 marks)
Write 'T' for a true statement and 'F' for a false one.
1. If one of the three bulbs connected in parallel circuit goes out, the other two bulbs still light up.
2. An electrical appliance with maximum current 5 A should be fitted with a 5 A fuse.
3. We should use three-pin plug because it can avoid overheating of the circuit when short circuit occurs.
4.    We can taste sulphuric acid in the laboratory.
5.    Metal saucepans should not be used to make ‘pork in ginger-vinegar’(豬腳薑).
6.    Acid rain corrodes constructions made of marble and metals.
7.    Acid can kill micro-organisms .
8.    Humans have five sense organs: eyes, ears, teeth, nose and skin.
9.    The movement of our eyeballs is caused by the actions of the eye muscles.
10.   In a dark place, the objects that we can see are clear and colourful.

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(C) Matching (10 marks)
           Column A                                                      Column B
1. fuse rating                             A.   a safety device to protect electrical appliances at home
2. mains voltage in Hong Kong              B.   ammonia
3. circuit breaker                         C.   to relieve stomach-ache
4. distilled water                         D.   unit is ampere
5. antacids                                E.   pH 7
6. sodium hydroxide                        F.   carries signal to retina
7. glass cleaners                          G.   240V
8. short sight                             H.   220V
9. long sight                              I.   to neutralize the acidic waste discharged from factories
10. optic nerve                            J.   cannot see distant objects clearly
                                           K.   cannot see near objects clearly

(D) Fill in the blanks (20 marks)
1. In a (a)_____________ circuit, the bulbs are connected in different branches. The current flows through
   more than one path.
2. Besides a circuit breaker, a (b)_____________ is also a safety device that will break the circuit if the
   electric current is (c) _________ than a certain value.
3. If the case of an electrical appliance is made of (d)_____________ , the (e)_____________ wire should be
      connected to the case of the electrical appliance.
4.    The switch and the fuse are connected to the (f)_____________ wire of an electrical appliance.
5.    It is dangerous to connect too many electrical appliances to the same socket as this would lead to
      (g) ______________.
6.    Generally, acids taste (h)______________ while alkalis taste (i)______________.
7.    A substance with a pH value of 2 is more (j)______________ than one with a pH value of 5.
8.    To measure pH values more accurately, we can use an instrument called (k)______ _______.
9.    (l)______________ _____________ and (m)____________ ______________ are the acidic pollutant
      gases in the atmosphere that cause the formation of acid rain.
10.   Normal rainwater is acidic because (n)__________ __________ is present naturally in the atmosphere.
11.   Vinegar can kill (o)______________ and thus can be used to (p)______________ food.
12.   The pupils in the eyes of all humans are (q) ___________ in colour.
13.   The space between the lens and the retina in the eye is filled with (r) _______________ __________.
14.   We cannot see things that are too close or too far away. These are examples of the (s) ________________
      of our eyes.
15.   A (t)________________ person cannot distinguish certain colours.

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(E) Structured Questions (40 marks)
1. The working current of several electrical appliances are shown below. They are all connected to the same
    socket with a fuse as shown in the diagram above.
       Electrical appliance        Working current
                 A                         7A                       A            B
                 B                         8A
                 C                        6.5 A                           C
                 D                        10 A
                 E                         9A                              D


(a) Which two electrical appliances are arranged in series? (2 marks)
(b) If A is broken and all the other appliances are switched on together, what would be the main current? (Show
    your work) (2 marks)
(c) Two ovens are damaged as shown in the figures below. The live wires are touching the metal cases of the
    ovens. Draw arrows in figures indicate how the currents flow from points P and Q to the ground.(3 marks)

                             Oven with earth wire                          Oven without earth wire

                                                                                               [Total : 7 marks]

2.   Read the article about cell phone explosion below and answer the questions.

                                            Cell phone explosion
           There are several cases of cell phone explosion occurred around the world recently. It is believed
     that the overheating of the cell phone battery is the main cause of the explosion.

           There are many causes of overheating of the battery. One of them is short circuit. Some fake (冒牌)
     cell phone batteries do not have safety device (安全裝置) to avoid short circuit, overheating may occur
     when there is damage in the cell phone, or when the battery in contact with conducting materials like
     keys and coins accidentally.

          It is advised that we should not use the cell phone in the humid (潮濕) places like the bathroom
     because this would increase the chance of short circuit. We should also keep the battery and the cell
     phone in a cool dry place.

(a) According to the news above, state two causes of short circuit of the cell phone. (2 marks)
(b) Explain why short circuit may lead to overheating of the battery. (4 marks)
                                                                                              [Total : 6 marks]

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3.   The graph below shows how the pH value of dilute hydrochloric acid changes with the volume of dilute
     sodium hydroxide added. A few drops of universal indicator were added.

(a) What was the use of universal indicator? (1 mark)
(b) From the graph, answer the following questions:
    (i) What was the pH value of the original dilute hydrochloric acid? (1 mark)
    (ii) What was the volume of dilute sodium hydroxide solution needed to neutralise the hydrochloric acid?
         (1 mark)
    (iii) What was the pH value of solution when 9 cm3 of dilute sodium hydroxide solution was added?
          (1 mark)
    (iv) Was the solution in (b)(iii) acidic, neutral or alkaline? (1 mark)
    (v) Explain your answer in (b)(iv). (1 mark)
(c) Write a word equation for the neutralisation involved. (Using the chemical name provided). (5 marks)
(d) What method can be used to obtain a dried product of the reaction? (1 mark)
(e) Describe the appearance of the dried product. (1 mark)
                                                                                           [Total : 13 marks]

4.   Anna wrote a ‘secret message’ following the procedure below.
     1 Mix 1/4 cup of                              2 Dip a cotton swab in
       baking soda with 1/4                          the mixture. Then
       cup of water.                                 write a message on a
                                                     piece of paper with
                                                     the cotton swab.
                     water              baking
     3 Let the                                     4 With a sponge,
       piece of                                      paint grape extract
       paper dry.                                    across the paper.

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(a) (i) In step 3, the ‘secret message’ cannot be seen. Why? (1 mark)
    (ii) In step 4, the ‘secret message’ is visible. Why? (2 marks)
(b) The experiment is repeated. Grape extract is replaced with the following liquids. What will you observe in
        the end? Why?
      (i) Distilled water (2 marks)
     (ii) Universal indicator (2 marks)
                                                                                             [Total : 7 marks]

5.  A boy looks at a bus at the bus stop. He can see the bus clearly when it is far away. However, he cannot
    see the bus clearly when it is at the bus stop.
(a) What kind of eye defect does the boy have? (1 mark)
(b) Suggest two causes of his eye defect. (2 marks)
(c) Draw TWO ray diagrams to show how his eye focuses at a near object and the correction of this eye defect.
    (4 marks)
                                                                                           [Total : 7 marks]
                                                End of Paper

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