The document contains summaries of several diagrams showing different scientific processes and experiments. It provides answers to questions about the diagrams, identifying variables, materials, observations, and conclusions. The key information summarized is that the document contains expert summaries and explanations of multiple scientific diagrams and experiments.

1. Diagram 6 shows copper refining using electrolysis
Q:........................................................P :......................................... .
DIAGRAM 3
[3 marks]
(a) On diagram 3, name P, Q and R by using the following information
Pure copper
Impure copper
Copper(II) sulphate
(b) State the energy changes in this electrolysis process
(c) Why metal P becomes thinner in the electrolysis process?
(d) State one use of electrolysis other than metal refining.
ANSWER:
(a) P : Impure Copper
Q : Pure Copper
R : Copper (II) sulphate solution 3
b) Chemical energy to electical energy
(c) P metal dissolve to form positive ion
(d) Metal extraction//Metal electroplating
R :.........................................................

2. Diagram 4 shows radioactive radiation in electrical field.
+ + + + +
U
V : -------------------------
- - - - - - -
T : -------------------------
Radioactive source
(a) Name radioactive rays T and V in Diagram 4
(b) (i) Which ray is positively charged?
(ii) Explain your answer in b(i)
(c) Which ray is used to sterile food before packaging?
(a) State the method that can be used to stop ray U from emit to the
environment?
ANSWER:
a) T : Beta ray V : Alpha ray
(b) (i) V ray/Alpha ray (ii) because it deflect to negative plate
(c) U ray/gama ray
(d) Placed in lead block//concrete container

3. Diagram 6 shows the arrangement of atoms in a steel.
(a) Name the atom
( i ) P :
( ii ) Q :
(b) What is the role of atom P in the steel above?
(c) State two new characteristics of the steel compared to the iron.
(d) Name one alloy other than steel.
ANSWER:
(a) (i) P : Carbon
ii) Q : Iron
(b) Foreign atoms/P/carbon prevents the atoms of pure metal from sliding
over one another
(c) Harder// stronger//resistant to corrosion (any two)
(d) Brass//Pewter//Bronze
Diagram 5 shows a cross section of human brain.
DIAGRAM 5
atom P
atom Q
A
B

4. Glass wool
(
Heat Heat
(a) Based on Diagram 5, name the structures labelled A and B.
(b) State one function of structure A .
(b) State two effects of drug abuse on the brain
ANSWER:
(a) A : Cerebrum
B : Cerebellum
1 m
(b) Control the voluntary action//control speech/hearing/vision
(c) Brain damage/depression/hallucination/stay awake or
active/decrease stress/Slow down the reaction time/lost sense of
smell/vision/becomes intellectuallyincapable(any two suitable answers)
(d) Cannot maintain posture and body balance
Diagram 2 shows an experiment to study the reactivity of metals when react
with oxygen.
Three types of metals X, Y and Z are used and the results are shown in the
Table 2.
Metal Observation
X Burns with bright light
Y Glows dimly
Z Burns moderately
TABLE 2
(a) Write down one inference that can be made from observation in Table 2
(b) State the following variables in this experiment.
Metal filling
Potassium manganate (VII) (Serbuk logam)
DIAGRAM 1

5. (i) Manipulated :…………………………………….
(ii) Constant :…………………………………………
(c) Based on the results in Table 2, arrange the reactivity of the metals
from the most reactive to the least reactive.
(d) If the metals used in this experiment are magnesium, zinc and iron,
predict what is metal X?
ANSWER:
(a) Metal X is the most reactive // Metal Y is the least reactive
(b) (i) Type of metal
(ii) Amount/Quantity/Mass of metal
(c) X, Z, Y
(d) Magnesium
Diagram 3 shows the formation of twins.
Diagram 2
(a) Name process P.
(b) Name the cell division at stage Q.
(c) Describe how the two embryos are formed.

6. (d) State one characteristic of the foetuses formed.
ANSWER:
(a) Fertilisation
(b) Mitosis
(c) The zygote formed divides into two cells , then separate and move
apart.
Each zygote continues to divide through mitosis, forming two
embryos. 1
(a) The foetus have the same genetic content// gender
Essay
1. There are two types of variation, continuous variation and discontinuous
variation.
(a) Give four differences between continuous variation and discontinuous
variation. [4 marks]
(b) Diagram 8 shows various characteristics of human being.
Ability to roll tongue Blood group
Variation
(Variasi)
Type of earlob Presence of dimples
DIAGRAM 8
Study the above characteristics. Explain how you would develop a concept
based on the information in Diagram 8
Your explanation of the concept should include the following:
· Identify two common characteristics [2 marks]
· Develop initial concept [ 1 mark]
· Give another example and a non-example in relation to the concept
[2 marks]
· State the actual concept [ 1 mark]
ANSWER:
(a)
Continuous variation Discontinuous variation

7. Does not show obvious differences
in characteristics
Shows obvious differences in
characteristics
Influenced by environmental
factors
Influenced by genetic factors
Not inherited Inherited
Form a normal distribution graph Does not form a normal
distribution graph
4 m
(b)
· Two common characteristics:
 Shows obvious differences in characteristics
 Influenced by genetic factors
· Initial concept:
Variation that shows obvious differences in characteristics and
influenced by genetic factors is discontinuous variation.
Another example : Fingerprint // type of hair
· Non-example : Height // weight
· Actual concept:
A discontinuous variation is a variation that shows obvious
differences in characteristics and is influenced by genetic factors.
2 (a) (i) Draw and label the arrangement of particles in copper and
bronze
(ii) Explain why bronze is harder than copper?
(b) Diagram 9 shows examples of alloys
Alloys
(Aloi)
DIAGRAM 9
Pewter
(Piuter)
Bronze
(Gangsa)
Brass
(Loyang)
Study the above examples. Explain how you would develop a concept
of alloy. Your explanation of concept should include the following:

8. · Identify two common characteristics
· Develop initial concept.
· Give other examples and non-examples in relation to the
concept.
· Explain the actual concept
ANSWER:
(a) (i) Able to draw and label the arrangement of particles in copper and
bronze.
copper
Copper atom
(ii) Layers of copper atoms can slide over one another when sheared.
Tin atoms in bronze prevent copper atoms from sliding easily over
1 m
one another.
(b) (i) Two common characteristics:
· Mixture of two or more metals//mixture of a metal with a
small amount
of non-metal
Harder // more rust resistance
(ii) Initial concept:
Substance made up of two or more metals (in different
percentage) and
have better physical characteristics than its pure metal is an
alloy
(iii) Another example : ( steel / duralumin)
Non – example : Aluminium / carbon
(accept any suitable answers)
(iv) Actual concept:
Alloy is a substance made up of two or more metals (in
different percentage)
and have better physical characteristics than its pure metal.
3 Study the following statement.
Copper atom
Tin atom
bronze

9. The height of students in a classroom varies from one student to another
student and there are many values between the shortest student and the tallest
student.
(a) Suggest a hypothesis to study the above statement.
(b) Describe an experiment to test your hypothesis in 10(a) according to the
following criteria.
I. Aim of the experiment
II. Procedure or method
III. Tabulation of data and sketch the graph
IV. Conclusion
ANSWER:
a) The height of a student shows a continuous variation.
b) i) to show that the type of the variation for the height of the students in a
class is a continuous variation.
ii) - the height of each student is measured and recorded.
- The height of the student is classified into appropriate categories in
the table.
- The number of students for each category is recorded in the table.
- A histogram is drawn based on the data recorded in the table
c)Tabulation of data
Height(cm)
No.Of
students
d)The height of a student in a class shows a continuous variation.
4. (a) State two sources of water pollution and two effects on the
environment
(b) The Environmental Department had received a complaint from
Kampung Indah’s residents regarding to variety species of fishes found
floating dead in the river. The result of the investigation made on the

10. sample taken from the river proves that the river was contaminated with
effluents from the nearby palm oil factory.
Explain three methods that could be done by the factory management
in order to eliminate the sewages produced. Your explanation should
base on the following aspect:
I. Identify the problem.
II. Explain three alternatives to conserve the river.
III. List two alternatives according to their priority.
ANSWER:
a) Disposal of rubbish / sewage / fertilizer / toxic substance/chemical
substance
Effects:
Kill aquatic organisms / destruction of habits / change the pH value of
the water / leads to lack of oxygen
b) i) the variety species of fishes found floating dead in the river
ii) heating liquid effluents from the factory before dispsing them into
the river
- Recycle effluents frm the factory into useful substances / animals
feed / compost fertilizer
- Burn the oil palm waste can lead to release of thick smoke.
iii)- treating liquid effluent
- Recycle solid effluent
- Burn the waste
5. Study the following statement:
Reaction of different metals with acid will produce different volume of gas.
You are given boiling tube, cork stopper, delivery tube glass trough, water,
magnesium
powder, zinc powder and dilute sulphuric acid.
(a) Suggest a hypothesis to investigate the above statement
(b) Describe an experiment to test your hypothesis in 10(a) based on the
following criteria
(i) Aim of the experiment

11. (ii) Identification of variables
(iii) List of apparatus and materials
(iv) Procedure and methods
(v) Tabulation of Data
ANSWER:
(a) Reaction of reactive metals with acid produce a higher volume of gas/
the more reactive the metal the higher the volume of gas produced
(b) (i) To study the reactivity of metals with acid
(ii) Manipulated variable: type of metal
Responding variable: volume of gas collected
Controlled variable: concentration of dilute sulphuric acid
(iii) boiling tube, cork stopper, delivery tube, glass trough, water,
magnesium powder, zinc powder, copper powder dilute
sulphuric
acid and test tube.
(iv) 1. 5 cm3 of dilute sulphuric acid is poured into a boiling
5. The volume of gas collected is recorded in a table.
(v) Tabulation of data
Type of metal Volume of gas (cm3)
Magnesium
Zinc
Copper
tube.
2. A spatula of magnesium powder is added into the boiling
tube.
3. The gas released is collected in a test tube.
4. Steps 1-3 is repeated using zinc and copper powder.