Introducing Science

Name: Time allowed:

Class: ( ) Date:

Marks: / 191

Part A - True or false

1. The knowledge about microorganisms helps scientists find ways to prevent diseases.


2. When using a fire extinguisher to put out a fire, we should aim at the lowest part of
the fire before squeezing the handle. 

3. When you break a beaker, you should dispose of the broken pieces in a ‘broken
glass’ container. 

4. Wire gauze and tripod are used to support a beaker being heated. 

5. We should not throw solid waste into a sink. 

6. When a Bunsen burner strikes back, a green flame and a hissing sound are observed.


7. We can use a displacement can and a measuring cylinder to measure the volume of
a small object with an irregular shape. 
8. We should not pour any liquids into the sink. 

9. A test tube holder can be used to hold a solid for heating. 

10. Ecology and geology are branches of science. 

11. Flammable substances should be kept away from heat and flame. 

12. Scientists only believe in an idea if they find evidence in experiments. 

13. X-ray is one of the examples of discoveries in human history. 

14. We do not need to manage the natural resources as they can replenished
continuously in Nature. 

15. Never pour the excess chemicals back into the reagent bottle. 

Part B - Fill in the blanks

16. (1 mark each)

Scientists work like detectives. They start with making careful (a)_____________.
They carry out (b)_____________ to collect (c)____________. Finally, they draw
(d)____________ from their experimental results.

17. (1 mark each)

The (a)________________________ found on the containers of chemicals warn us
the potential dangers of the chemicals. (b)____________ chemicals should be kept
away from heat and flame. (c)____________ chemicals should be stored in a well
ventilated room while shock should be avoided when handling (d)____________
chemicals. When we handle harmful, (e)____________ or (f)____________
chemicals, we should avoid breathing in the vapour and we should wash our hands
thoroughly after handling these chemicals.

18. (1 mark each)

Three conditions are needed for a fire to start. They are (a)____________,
(b)____________ and (c)________________________. These three conditions
together make up the (d)________________________.

19. Fill in the blanks with the most suitable words chosen from the box below.
(1 mark each)
balance centimetres kilometres kilograms
grams clock stopwatch metre rule

(a) We usually use a (i)__________________________ to measure length. Short

lengths are measured in (ii)__________________________ or millimetres.
(b) In measuring mass, we can use a (i)__________________________. Our mass is
usually measured in (ii)__________________________.
(c) We usually use a __________________________ to measure time in the
laboratory.

20. (1 mark each)

To reduce the (a)____________ when we make measurements, we often repeat the
measurement several times and then calculate an (b)____________ value.

21. (1 mark each)

Temperature is usually measured in (a)_________________, which has a symbol
(b)_____________.

22. (1 mark each)

(a)____________ and (b)___________________ are the liquids commonly used in
thermometers.
23. We can use a ___________________ to measure temperature.

24. We can use a ______________ to stir liquids.

25. An electronic balance has a ‘____________’ function. This function is useful

when we need to measure the mass of a substance in a container.

Part C - Matching

26. Match column A with column B by writing the corresponding letters a, b, etc. in
the boxes below.
Column A Column B

1. fossil fuels  (a) resources that cannot be replenished in a

short time once they are used up

2. renewable resources  (b) can change light energy from the Sun to
electrical energy

3. non-renewable  (c) examples of renewable resources

resources

4. solar panels  (d) a type of non-renewable natural resource

that can be burned to give a lot of energy

5. plants and animals  (e) resources that can be replenished

continuously in Nature and will not be
used up

27. Match column A with column B by writing the corresponding letters a, b, etc. in
the boxes below.

Column A Column B

1. astronomy  (a) studying the Sun, the Moon, the stars and
 the Universe

2. biology  (b) studying the structure of the Earth and the

way it changes

3. geology  (c) studying the properties, composition,

structure and reactions of matter

4. physics  (d) studying living things

5. medicine  (e) studying matter, energy and forces

6. chemistry  (f) studying the human body and diseases

28. Match column A with column B by writing the corresponding letters a, b, etc. in
the boxes below.
Column A Column B

1. Bunsen burner  (a) to stir the liquid inside a beaker or flask

2. test tube  (b) to measure temperature

3. dropper  (c) for filtration

4. displacement can  (d) to transfer a small amount of powder to

another container

5. reagent bottle  (e) to hold test tubes

6. thermometer  (f) to hold liquid to be used soon

7. test tube rack  (g) to protect your eyes

8. sand bucket  (h) to measure the volume of a liquid

9. measuring cylinder  (i) to heat or burn things in the laboratory

10. safety goggles  (j) to transfer a small amount of liquid

11. glass rod  (k) to store chemicals

12. spatula  (l) to put out fire

13. filter paper  (m) to hold a test tube for heating

14. test tube holder  (n) to measure the volume of some
irregular-shaped objects

15. stopwatch  (o) to measure small time intervals

Part D - Online Test

29. Which of the following will NOT happen when the Bunsen burner strikes back?
A. A purple flame is observed.
B. A green flame is observed.
C. A hissing sound is heard.
D. The chimney is very hot. 

30. Angel is making some cookies. She wants to add 0.85 L of milk to the flour.
However, the volume markings of the measuring jug are in cm3. How much milk in
cm3 she has to add?

A. 8.5 cm3
B. 85 cm3
C. 850 cm3
D. 8500 cm3 

31. The correct steps of lighting a Bunsen burner are:

A. open the air hole, turn on the gas tap, place the gas lighter above the chimney and
press its button.
B. close the air hole, turn on the gas tap, place the gas lighter above the chimney
 and press its button.
C. close the air hole, place the gas lighter above the chimney and press its button,
turn on the gas tap.
D. place the gas lighter above the chimney and press its button, open the air hole,
turn on the gas tap. 

32. Which of the following materials are inventions?

(1) Copper
(2) Plastic
(3) Paper
A. (1) and (2) only
B. (2) and (3) only
C. (1) and (3) only
D. (1), (2) and (3) 

33. What should you do if your classmate gets an electric shock in the laboratory
when doing an experiment?
(1) Immediately pull him away from the source of electricity by hands.
(2) Cut off the power supply.
(3) Report to your teacher at once.
A. (1) only
B. (1) and (2) only
C. (2) and (3) only
D. (1), (2) and (3) 

34. Which of the following diagrams shows the correct way of heating water in a test
tube?
A. B. C. D.

 
35. When we turn the collar of the Bunsen burner, we can adjust the Bunsen flame.
This is because
A. the amount of air supplied to the Bunsen burner changes.
B. the amount of gas fuel supplied to the Bunsen burner changes.
C. the temperature of the Bunsen flame changes.
D. the shape of the Bunsen burner changes. 

36. 1200 mm is equal to

A. 1.2 cm.
B. 12 cm.
C. 120 cm.
D. 1200 cm. 

37. According to the diagrams below, what is the change in mass of the liquid in the
evaporating dish?

after 1 week

A. Increased by 50 g
B. Decreased by 50 g
C. Increased by 100 g
D. Decreased by 100 g 

38. If a Bunsen burner strikes back, we should

A. turn off the gas tap.
B. turn on the air hole.
C. turn off the air hole.
D. block the air hole. 

39. Which of the following is/are (an) observation(s)?

(1) An apple turns brown when it is cut and exposed to air.
(2) There is a substance in the apple that may cause the apple to turn brown.
(3) An apple that is cut does not turn brown when it is placed in salt water.
A. (1) only
B. (2) only
C. (1) and (3) only
D. All of the above 

40. Scientists around the world have developed vaccines (疫苗) to protect people
against COVID-19. However, most scientists believed that the vaccines do not
provide full (100%) protection.

From this example, we know that scientific knowledge

A. can cause harm if it is not used properly.
B. is subject to change.
C. has its limitations.
D. can only be used to develop technology. 

41. The photo below shows the Olympic torch’s flame.

Which of the following statements about the Olympic torch’s flame is correct?
A. It is a luminous flame and it has a regular shape.
B. It is a luminous flame and it has an irregular shape.
C. It is a non-luminous flame and it has a regular shape.
D. It is a non-luminous flame and it has an irregular shape. 

42.

When we start a barbecue fire, we usually fan the fire,

A. this provides more oxygen to the fire for burning.
B. this lowers the temperature of the barbecue fire and thus lower the risk of an
accident.
C. this increases the temperature of the barbecue fire and so the fire can be stronger.
D. this brings more fuel to the fire for burning. 

43. Julia pours some hot water into a metal can. She measures the water temperature
(in degrees Celsius) at 1-minute intervals and draws a graph to represent her results.
 y

x
How should she label the x-axis and y-axis respectively?
x-axis y-axis
A. time (min) temperature (oC)
B. time (min) temperature (degrees)
C. time temperature
D. temperature (oC) time (min)


44. Which of the following is/are usually used as the liquid in a thermometer?
(1) Water
(2) Coloured alcohol
(3) Mercury
A. (1) only
B. (2) only
C. (2) and (3) only
D. (1), (2) and (3) 

45. The diagram below shows a digital caliper. It is a measuring device with precision
up to 3 decimal places.

(a) What is the diameter of the circular pipe in the photo?

A. 1.031 inch
B. 10.31 inch
 C. 1.031 cm
D. 10.31 cm 

(b) It is given that 1 inch equals to 2.54 cm. What is the diameter of the circular pipe
in mm?
A. 2.464 mm
B. 24.64 mm
C. 26.19 mm
D. 2.619 mm 

46. Which of the following are non-renewable resources?

(1) Water
(2) Metal ores
(3) Air
(4) Fossil fuels
A. (1) and (2) only
B. (1) and (3) only
C. (2) and (4) only
D. (3) and (4) only 

47. Which of the following is NOT an example of observation?

A. Water evaporates.
B. Ice floats on water.
C. Leaves are green.
D. Rice can give us energy. 

48. The following is the normal procedure that a scientist will take for performing a
research.
1. Observe carefully
2. Identify the problems to be investigated
3. ?
4. Do experiments
5. ?
6. Record in detail
7. ?
8. Think about the results and discuss with each other
9. ?
The missing steps are as follows:
(a) Draw conclusion
(b) Predict
(c) Measure accurately
(d) Analyse
Which one is the correct sequence of the missing steps?
Step 3 Step 5 Step 7 Step 9
A. (a) (b) (c) (d)
B. (b) (c) (d) (a)
C. (b) (d) (c) (a)
D. (d) (c) (b) (a)


49. Which of the following statements about making measurement is INCORRECT?

A. The instruments with smaller interval divisions are more precise.
B. There will be no error by repeating the measurement several times and
calculating an average value.
C. The measurement data can be presented by using a table.
D. The measurement data can be presented by using a graph. 

50. In North America and Europe, temperature is usually measured in Fahrenheit (°F).
The conversion between degree Fahrenheit and degree Celsius can be calculated using
the following formula:
9
F= t + 32 (t is the temperature measured in degree Celsius)
5

If the temperature of New York City today is 77 °F, then the temperature in degree
Celsius is about
A. 10 °C.
B. 13 °C.
C. 25 °C.
D. 40 °C. 

51. Which of the following statements about using a thermometer is INCORRECT?

A. When measuring temperature, you need to choose a thermometer with a suitable
measuring range.
B. When measuring the temperature of a liquid, the bulb of the thermometer has to
touch the bottom of the container.
C. Do not take the reading immediately after the thermometer is put into the liquid.
D. When taking the reading, make sure your eyes are at the same level with the
reading. 

52. Directions: Questions (a) and (b) refer to the following information.

Tammy wants to investigate how different liquids oppose the falling motion of an
object. In her investigation, she plans to release a marble into three measuring
cylinders containing different liquids. The experimental set-ups are shown below.

corn oil water honey

I II III

(a) Which of the following is/are the variable(s) that Tammy will change?
(1) Volume of the liquid
(2) Type of liquid
(3) Temperature of liquid
A. (1) only
B. (2) only
C. (1) and (3) only
D. (2) and (3) only 

(b) Which of the following is the variable that Tammy will measure?
A. The mass of the marble
B. The rise in the liquid level when the marble reaches the bottom of the cylinder
C. The change in the mass of the set-up
D. The time taken for the marble to fall to the bottom of the cylinder 

53. Which of the following methods CANNOT put out a fire?

A. Pouring a bucket of sand onto the fire
B. Spraying water onto the fire
C. Applying carbon dioxide to the fire
D. Applying oxygen to the fire 

54. Which of the following objects has the largest mass?

A. 10 g of iron
B. 1000 g of water
C. 1500 g of water
D. 1 kg of feathers 

55. What is the volume of this object?

radius (半徑) = 2 cm

3 cm

2 cm

3 cm

5 cm

A. (30 + 9π) cm3

B. (30 + 12π) cm3
C. 42 cm3
D. 36 cm3 

56. A scientist studies the relationship between the temperature of water and its
density (密度). The experimental results are shown in the graph below.

0.9999

density of
water 0.9998
(g/mL)

0.9997

0.9996
0 2 4 6 8 10 12
temperature of water (C)

(a) What can you conclude from the experimental results?

A. The density of water is independent of its temperature.
B. The higher the temperature of water, the lower its density.
C. The density of water is the highest at 4 °C.
D. Apart from temperature, the density of water is affected by other factors. 

(b) What is the independent variable in this experiment?

A. The density of water
B. The temperature of water
C. The volume of water
D. The mass of water 

57. The photo below shows a thermometer with both scales of degrees Celsius (°C)
and degrees Fahrenheit (°F).
Which of the following shows the correct temperature readings in both scales?
degrees Celsius (°C) degrees Fahrenheit (°F)
A. 2 40
B. 0 40
C. 4 40
D. 40 4


58. Directions: Questions (a) and (b) refer to the following information.
Louis is given some sugar, salt and corn flour. He wants to find out which substance
will dissolve the fastest in 100 cm3 of water at room temperature.

(a) Which of the following can be hypotheses for the investigation?

(1) Sugar dissolves the fastest in the water.
(2) Corn flour dissolves the slowest in the water.
(3) Does the volume of water affect the time taken for the substance to dissolve?
A. (1) and (2) only
B. (1) and (3) only
C. (2) and (3) only
D. (1), (2) and (3) 

(b) Which of the following is the correct combination of variables for the
experiment?
Control variable Independent variable Dependent variable
A. Temperature of water Time taken for the Types of substance
substance to dissolve to be dissolved
B. Types of substance to Volume of water used Time taken for the
be dissolved substance to dissolve
C. Volume of water used Time taken for the Temperature of water
substance to dissolve
D. Temperature of water Types of substance Time taken for the
to be dissolved substance to dissolve


Part E - Short question

59. What units is suitable for measuring each of the following?

(a) Volume of a can of Coke (1 mark)

_________________________________________________________________

(b) Mass of a man (1 mark)

_________________________________________________________________

(c) Temperature of ice (1 mark)

_________________________________________________________________

(d) Length of an aeroplane (1 mark)

_________________________________________________________________

60. The graph below shows the distance travelled by James’s car in a trip to his
uncle’s house, which is 100 km away from James’.

y-axis

x-axis

(a) How should the x-axis be labelled? (1 mark)

_________________________________________________________________

(b) How should the y-axis be labelled? (2 marks)

_________________________________________________________________

(c) Estimate the starting time of James’s trip. (1 mark)

_________________________________________________________________

(d) What is the distance travelled by James’s car at 11:00 am? (1 mark)
_________________________________________________________________

61. State TWO ways in which a scientist works like a detective. (2 marks)
_____________________________________________________________________
_____________________________________________________________________

62. Thin metal sheets are usually rolled into a cylindrical shape when they are
manufactured in factories.

one metal sheet

rolled into a
cylindrical shape

If the metal sheets are not rolled open, how can you know the total length of the metal
sheet? (4 marks)
(Hint: You may make some measurements of a small piece of metal sheet first.)

total length of the metal sheet

rolled open

_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________

63. Danny has bought a bottle of domestic cleansing agent. He finds that the container
has the following hazard warning symbol.

(a) What potential hazard does the cleansing agent have? (1 mark)
 _________________________________________________________________

(b) Write ONE safety precaution that Danny should take when he uses the cleansing
agent. (1 mark)
_________________________________________________________________

(c) What immediate action should Danny take if the above chemical is in contact
with his skin? (1 mark)
_________________________________________________________________

64. Jacky measures his pulse rate (脈搏率) after doing different numbers of push-ups.
The results are shown below.
Number of 0 5 10 15 20 25
push-ups
Pulse rate 70 77 84 92 100 110
(beats per minute)

(a) What can you conclude from the above results? (1 mark)
_________________________________________________________________

(b) Susie has the following comment on the experiment.

To save time, Jacky should do another round of

push-ups immediately after every measurement.

Do you think Susie is correct? Explain your answer. (2 marks)

_________________________________________________________________
_________________________________________________________________

65. Study the diagram below.

 add 6 equal-sized marbles

What is the volume of each marble? (1 mark)

_____________________________________________________________________

66. Write the names of the safety equipment found in a laboratory below.
(a) (b) (c)

____________________ ____________________ ____________________

Part F - Long question

67. In a body test, Mr. Cheung is asked to ride a bicycle. His heart rate is measured
and recorded every minute. The results are shown in the graph below.
 Heart rate
(Beats per minute)

Time (minutes)

(a) What instrument should be used to measure time in the experiment? (1 mark)
_________________________________________________________________

(b) What is the resting heart rate of Mr. Cheung? (1 mark)

_________________________________________________________________

(c) Estimate in which period Mr. Cheung is riding the bicycle. (2 marks)
_________________________________________________________________

(d) What is the highest heart rate of Mr. Cheung in the test? (1 mark)
_________________________________________________________________

(e) How long does it take for Mr. Cheung’s heart rate to return to resting heart rate
from the highest rate? (1 mark)
_________________________________________________________________

68.
Read the following article and answer the questions that follow.

Using Mice in Drug Tests

Scientists develop many new drugs for disease treatment every year. Before these drugs
are taken to clinical trials (臨床試驗) on patients, they are often tested on mice. A
common method is to keep two groups of mice in the laboratory. Only one group is
given the drug while the other group is not.

If the drug to be tested is a cancer drug, the two groups of mice will first be injected with
the cancer cells. Then, they are given the drugs and after a few days, blood samples will
be collected from the two groups of mice to test for the presence of anti-cancer cells.

(a) Which group of mice is the ‘control group’ 「

( 對照組別」) and which group is the
‘experimental group’? (2 marks)

(b) Referring to the cancer drug test,

(i) form a hypothesis. (1 mark)

(ii) state the independent variable and the dependent variable. (2 marks)

(iii) suggest TWO control variables. (2 marks)

(c) Using mice in drug tests is necessary for the safety of new drugs. However, some
 people oppose these tests. Suggest a reason. (1 mark)

69. Below shows a clinical thermometer that can be used to measure body
temperature.

glass

liquid

Other than clinical thermometers, ear thermometers are also used in some clinics.

glass thermometer

ear thermometer

(a) What is the highest temperature that the clinical thermometer shown above can
measure? (1 mark)
_________________________________________________________________

(b) Which liquid is usually used as the liquid column in clinical thermometers? (1 mark)
_________________________________________________________________

(c) Does the volume of liquid in the clinical thermometer change during
measurement? Briefly explain. (2 marks)
_________________________________________________________________
_________________________________________________________________

(d) Does the mass of liquid in the clinical thermometer change during measurement?
Briefly explain. (2 marks)
_________________________________________________________________
_________________________________________________________________
(e) Give a reason why it is safer to use an ear thermometer than a clinical
thermometer. (1 mark)
_________________________________________________________________

70.
John reads from a cook book that raw tough
meat can be softened by fruit juice. He carries
out an experiment to study the meat softening
ability and find out which kind of juice has
the best meat softening ability. His
experimental set-ups is shown below.

fruit juice A fruit juice B fruit juice C distilled water

meat cubes

(All the meat cubes in the set-ups are the same.)

After 10 minutes, he cooks the meat under the same condition and asks five of his
friends to taste the meat.

(a) State a possible hypothesis for John’s investigation. (1 mark)

(b) Suggest an independent variable, a dependent variable and any three control
variables in John’s investigation. (5 marks)
Independent variable Dependent variable Control variables
(c) Suggest why John asks five of his friends to taste the meat rather than just one.
(1 mark)

(d) Suggest why testing meat softening ability of fruit juice by tasting may not give
fair results. (1 mark)

(e) Suggest a reason why there is a set-up using distilled water. (1 mark)

71. The diagrams below show two cards. They were heated for five seconds by two
types of Bunsen flame.

black hole
soot

A B black
soot

(a) Name the Bunsen flame used in A and B respectively. (2 marks)

A: ______________________________________________________________
B: ______________________________________________________________

(b) Why is there a hole in B but not in A? (2 marks)

________________________________________________________________
________________________________________________________________
72. Do you think the following people think in a scientific way? If not, explain why.
(3 marks)
(a)
Michael won the first prize of Christmas lucky
draw last year and the year before. I think he is
going to win the first prize again this year.

_________________________________________________________________
_________________________________________________________________
_________________________________________________________________

(b)

Several of my friends said that their children get

good results in examination after wearing crystal
bracelet (水晶手鐲). This shows that crystal
helps one study better.

_________________________________________________________________
_________________________________________________________________
_________________________________________________________________

(c)
 One day I Lamp A
switched on
lamp A but
the light bulb light
does not bulb
glow. I think
the bulb
burned out.

Lamp B
But when I
try to install
Glows
the same bulb
to lamp B, it
glows.
light
bulb

Therefore, I think lamp A is out of order and

so I take it to repair.

_________________________________________________________________
_________________________________________________________________
_________________________________________________________________

73. Make an inference for each of the following. (An inference is an explanation you
can give based on your observations.)

(a) There is broken glass at the intersection of the roads. (1 mark)

_________________________________________________________________
_________________________________________________________________

(b) The leaves on the tree have many holes in them. (1 mark)
 holes

_________________________________________________________________
_________________________________________________________________

(c) The dog in the house next door is barking in the middle of the night. (1 mark)
_________________________________________________________________
_________________________________________________________________

(d) You wake up suddenly in the middle of the night. You hear a faint scratching
noise from the wall. (1 mark)
_________________________________________________________________
_________________________________________________________________

(e) Many ants are gathering at a stain on the floor. (1 mark)

_________________________________________________________________
_________________________________________________________________

74. The table below shows the mass of water, fat, dietary fibre and vitamin C in
potatoes cooked in different ways.
Dietary Vitamin C
Water (g) Fat (g)
fibre (g) (mg)
100 g of potato chips 62 6 0 8
10 g of boiled potato
8.1 0 0.1 0.7
(without skin)
50 g of baked potato
32 0 1.5 7.5
(with skin)

(a) How many grams of water are there in 350 g of boiled potato? Show your
calculations. (2 marks)
_________________________________________________________________
_________________________________________________________________

(b) Which type of cooked potato contains the largest amount of vitamin C per 100 g
of potato? Show your calculations. (4 marks)
 _________________________________________________________________
_________________________________________________________________
_________________________________________________________________
_________________________________________________________________

75. Write each of the following readings: (8 marks)

(a)

__________________ cm

(b)

__________________ mm

(c)
__________________ km

(d)
 __________________ cm3

(e)

__________________ C

(f)
__________________ km/h

(g)
 __________________ kg

76. Amy wants to find out the conditions needed for seed germination (種子發芽).
She puts forward the following hypothesis:
Seeds need oxygen, water and warm temperature for germination.

(a) Amy sets up the following apparatus to test her hypothesis.

refrigerator
A B C

substance
that
removes
oxygen
seed

moist cotton wool moist cotton wool

However, her teacher points out that one more test tube should be added. What is
the set-up of this test tube? Draw it in the space below. (2 marks)
(b) Complete the following table to show the conditions of test tubes A, B, C and the
added test tube. (4 marks)

Test tube
Condition
A B C Added
Water
Oxygen
Warm
temperature
(Put a ‘’ if the condition is present in the test tube. If not, put a ‘’ .)

(c) If Amy’s hypothesis is correct, in which of the above test tubes would the seeds
germinate? (1 mark)
_________________________________________________________________