Singapore Primary Science Olympiad
THEORY ROUND
Instructions to Candidates
1. Do not open the booklet until you are told to do so.
2. Answer ALL 40 questions
3. Write your answers in the answer sheet provided and shade the appropriate bubbles
below your answer.
4. Questions 1 – 30 are worth 1 mark each.
5. Questions 31 – 40 are worth 2 marks each. For each of the questions, three statements 1
to 3 are provided. Students have to decide whether each of the statements is or is not
correct.
The responses A to D should be selected based on:
A
B
C
D
1, 2 and 3
are correct
1 and 2 only
are correct
2 and 3 only
are correct
1 only
is correct
6. No mark will be deducted for a wrong answer.
7. Unanswered questions will not get any marks.
Section A
For each question, four options are given. Only one of them is the correct
answer.
Choose the most suitable answer and shade your answer clearly on the Optical
Mark Sheet (OMS) provided. Each question carries 1 mark.
1. Which of the following statements describes substances which are gases at
room temperature?
A. Their boiling point is below room temperature, but their melting point is
above.
B. Their boiling point is above room temperature, but their melting point is
below.
C. Their boiling and melting points are both above room temperature.
D. Their boiling and melting points are both below room temperature.
2. The figure below shows an apparatus set up to investigate the rate of
photosynthesis of water weeds.
Which of the following will not increase the rate of photosynthesis?
A. Increase in light intensity
B. Increase in temperature to 40 °C
C. Increase in oxygen concentration
D. Increase in concentration of mineral salts in the water
3. In a container, water and ice are found to exist together. What is most likely
to be the temperature of the container?
A. Less than 0 oC
B. Around –4 oC
C. 4 oC
D. Exactly 0 oC
4. Coal remains as one of our most precious sources of energy today. Coal
contains elements like carbon, hydrogen, oxygen and sulfur. The element in
coal that gives it the energy content is carbon. Four types of coal were
analyzed for their composition. The results are given below. Which of the type
of coal below gives the highest energy content?
Type of Coal Carbon (g) Hydrogen (g)
A.
B.
C.
D.
Flame Coal
Anthracite
Lignite
Forge Coal
4
4.8
6
9
0.3
0.17
6
4
Oxygen
(g)
0.5
0.12
34
3
Sulphur(s)
0.05
0.05
0.4
0.1
5. Animals X, Y and Z are found in completely different habitats. Animal X is
nocturnal and has developed many characters to conserve as much water as
possible in the body. Animal Y has furry body with thick skin. It is large in size
and has padded feet. Animal Z is adapted to live on trees, sticky pads on its
feet help it climb trees. Which of the following can you conclude regarding the
habitats of these animals?
A. Animal X lives in a place with annual rainfall of about 80 cm – 100 cm.
B. Animal Y lives in a place where days may be extremely hot and nights can be
very cold.
C. Animal Z lives in area with annual rainfall of about 20 cm – 25 cm.
D. Animal Y lives in an area where temperature sometimes reach 0°C or fall
below it.
6. Neutral insulator P is rubbed with neutral insulator Q. Insulator P becomes
positively charged after the rub. Which of the following statements is correct?
A. P loses some electrons to insulator Q.
B. Q loses some electrons to insulator P.
C. P gains positive charge from insulator Q.
D. Q gains positive charge from insulator P.
7. A body immersed in a fluid experiences an upward thrust which depends on
A. The weight of the fluid displaced by it.
B. The volume of the body.
C. The mass of the body.
D. All of these.
8. When Cu is exposed to moist air for a long time, which of the following is
formed?
A. Cu(OH)2
B. CuCO3
C. Both A and B
D. Cu2O
9. Run-off pollution of a particular river resulted from overuse of chemical
fertilizers by a nearby farm. Which of the following graphs correctly shows the
resulting changes in levels of oxygen and bacteria in this river?
10. Alex has performed an experiment to compare the strength of different
fibres. He arranged the set-up as shown in the figure below. Arrange the
threads in order of their increasing strength.
A. Nylon < Silk < Cotton
B. Silk < Cotton < Nylon
C. Cotton < Nylon < Silk
D. Cotton < Silk < Nylon
11. Jane was studying the growth of yeast under different conditions of
environment. She plotted two graphs but forgot to label the X axes of the
graphs. Analyse the given graphs and select the correct option.
A. The environmental factor studied in graph P can be pH and in graph Q can
be temperature.
B. The environmental factor studied in graph P can be temperature and in
graph Q can be sugar concentration in medium.
C. The environmental factor studied in graph P can be temperature and in
graph Q can be pH.
D. The environmental factor studied in the graph P can be sugar concentration
in medium and in graph Q can be pH.
12. Filtration as a method of separation can be used for mixtures that are
A. Homogeneous and liquid-in-gas mixtures.
B. Heterogeneous and liquid-in-liquid mixtures.
C. Homogeneous and solid-in-liquid mixtures.
D. Heterogeneous and solid-in-liquid mixtures.
13. The freezing and boiling points of a substance P are – 220°C and – 185°C
respectively. At which of the following range of temperatures will P exist as a
liquid?
A. Between – 175°C and – 210°C
B. Between – 190°C and – 225°C
C. Between – 200°C and – 160°C
D. Between – 195°C and – 215°C
14. Four strips of fresh potato P, Q, R and S were immersed in solutions of
different concentrations. Osmosis occurred according to the concentration
difference between cell sap and ambient solution. A graph was plotted
between initial length of strips and the change in length after osmosis. Which
of these strips was placed in the most diluted solution?
A. S
B. Q
C. R
D. P
15. A food web is given below:
How many primary consumers and secondary consumers are involved in the
food web, respectively?
A. 2 and 3
B. 2 and 4
C. 3 and 3
D. 3 and 4
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
Section B
For each question in this section, one or more of the three numbered
statements 1 to 3 may be correct. The responses A to D should be selected on
the basis of:
A
B
C
D
1, 2 and 3
are correct
1 and 2 only
are correct
2 and 3 only
are correct
1 only
is correct
No other combination of statements is used as a correct response. Each
question is worth 2 marks. No mark will be deducted for a wrong answer.
31. Which of the following statement(s) is a hypothesis (are hypotheses)?
1. If KMnO4 crystals are heated above the decomposition temperature,
240 oC, they will give off oxygen gas.
2. If pure gold had a density of 0.8 g/cm3, instead of 22 g/cm3, then it
would float on water.
3. If iron were as easy to extract from its ores as copper, then its use would
have begun much earlier in history.
32. The diagram below shows the circulatory system in a human body.
After a lunch meal, what happens to blood vessel M when compared with that
of blood vessel N?
1. Blood vessel M carries more oxygen.
2. Blood vessel M carries less carbon dioxide.
3. Blood vessel M carries more digested food.
33. What can we infer when an object floats on water?
1. The object must be less dense than water.
2. The object must be able to float in oil.
3. The object must be submerged with half its volume in water.
34.
1. S1
2. S3
3. S4
35.
36.
1. Release the toy car from C instead of A
2. Increase the distance from D to E
3. Use a ramp with a rougher surface
37. Which of the following appliances will produce heat when turned on?
1. Fan
2. Fridge
3. Personal Computer
38.
1. A
2. B
3. D
39.
1. A
2. B
3. D
40.
1. Overcome the attractive forces between the water molecules.
2. Increase kinetic energy of the water molecules
3. Break the chemical bonds in water molecules
Answer Key
1. D
2. D
3. C
4. D
5. D
6. A
7. A
8. C
9. A
10. D
11. B
12. D
13. D
14. C
15. C
16. A
17. B
18. A
19. A
20. B
21. C
22. B
23. C
24. D
25. B
26. A
27. A
28. C
29. A
30. A
31. D
32. B
33. D
34. B
35. C
36. A
37. A
38. C
39. C
40. D