F.3 Chemistry Revision Worksheets / First Term / 2005 –2006 / Page 1
HKCWCC
(1) Which of the following substances is an element?
(A)
Ice
(B)
Coal
(C)
Iron
(D)
Sand
The Answer is in the last page,
Page 4
(2) Which of the following is the most abundant metal in the Earth’s crust?
(A)
Aluminium
(B)
Oxygen
(C)
Iron
(D)
Nitrogen
(3) Which of the following statements about the element oxygen is FALSE?
(A)
Oxygen is the most abundant element in nature.
(B)
Oxygen exists in combined forms with other elements.
(C)
The abundance of free oxygen in the Earth’s crust is unique in the Solar System.
(D)
Oxygen is flammable.
(4) Which of the following is NOT a use of carbon dioxide?
(A)
It can be used to make fire extinguishers.
(B)
It is put into soft drinks,
(C)
It is used to fill light bulbs.
(D)
It is used as a refrigerant.
(5) If some dilute hydrochloric acid gets into a student’s eye while doing an experiment, the first thing he
should do is to
(A)
report to the supervising teacher at once
(B)
wash his eye with dilute sodium hydrogencarbonate solution
(C)
dial 999 for help
(D)
wash his eye with running cold water
F.3 Chemistry Revision Worksheets / First Term / 2005 –2006 / Page 2
HKCWCC
(6) Refer to the experimental setup as shown below :
A
B
C
mixture of liquids P,Q and R
(a) Name the process as shown in the diagram.
(1 mark)
(b) Label the diagram A,B and C.
(3 marks)
(c)
Liquids
boiling points (oC)
P
80
Q
100
R
120
According to the boiling points as shown in the table, which liquid will be distilled first ? Explain
your answer briefly.
(2 marks)
(d) At the end of the experiment, the ‘C’ collected is not very pure. Suggest a method to increase its
purity.
(2 marks)
F.3 Chemistry Revision Worksheets / First Term / 2005 –2006 / Page 3
HKCWCC
(7) Peter, a Form 3 student, is asked to carry out an experiment to separate a sample of solids containing
sand and iodine. Suggest how Peter should carry out the experiment.
(3 marks)
(8) Sea water contains a certain amount of the chemical sodium chloride. Briefly describe the experimental
steps that you can get the pure water and pure salt from the sea water.
Name this process.
(4 marks)
(9) Experiments were carried out to investigate the chemical properties of a mixture and a compound
A
B
mixture of sulphur powder and iron filing
a compound of sulphur and iron
(a) Give the chemical name of B.
(1 mark)
(b) Describe the action of a magnet on A and B respectively.
(2 marks)
(c) Describe briefly, what happens when dilute acid is added to A and B respectively.
(2 marks)
(d) What are the chemical properties of A and B comparing with its constituent elements?
(2 marks)
(10) On the plastic bags provided by a supermarket to the customers, the following statement is printed:
“This plastic bag is made of plastic that can be recycled.”
(a) Do you think the supermarket has made any effort to protect the environment? Explain your
answer.
(b)
(2 marks)
Suggest a statement that can be printed on the plastic bags to encourage customers to reduce the
use of plastics.
(1 marks)
F.3 Chemistry Revision Worksheets / First Term / 2005 –2006 / Page 4
HKCWCC
Answer for the Re. WS
1
C
2
A
3
D
4
C
5
D
6a
The process is called Fractional Distillation
6b
A : Thermometer
B : Condenser
C : Distillate
6c
P will be distilled first.
It is because it has the lowest / a lower boiling point.
6d
Repeat the experiment with the distillate.
7
The mixture is heated over a Bunsen flame.
Only the iodine solid will sublime into a vapour, while the sand remains unchanged upon heating.
The iodine vapour is cooled and collected on a cold glass surface.
As a result, sand and iodine is separated.
8
The process is called Distillation.
The sea water is heated over a Bunsen flame. When it boils, steam is directed into a condenser
where it is cooled down by the surrounding. As the steam condenses back to water, it is collected in a
beaker as the distillate. Salt is remained in the flask.
9a
The chemical name of B is iron (II) sulphide.
9b
For A, only the iron is attracted by the magnet while sulphur is not.
For B, it is not attracted by the magnet.
c
For A, hydrogen gas is produced / colour gas liberates and burn with a ‘pop’ sound.
For B, hydrogen sulphide gas is produced / a bad smell gas is produced.
d
A still retains the original chemical properties as its constituent elements.
B has entire different properties from its constituent elements.
10a Yes, it has. It is because the supermarket has used a certain new substance which can be recycled to
replace the old plastic.
10b “Save our Earth, reduce using plastic !!!”