Leave blank
Name
________
8 “___________”
Grade
45
End of the Term 3 Exam
Science
"
_ __________ " 2013
Time allowed: 1 hour
READ THESE INSTRUCTIONS FIRST
Write your name properly.
FOR EXAMINER’S USE
Use a blue or black ball-point pen.
1
Do not use correction fluid, staples, paper clips, highlighters or glue.
2
The exam paper must be returned to the teacher.
3
pg. no
4
Answer all questions.
5
6
If working is needed show it in the space below that question.
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8
INFORMATION
The maximum mark for tasks is 45.
9
10
11
12
Total
Invigilator: __________________________
Signature: __________________________
Checked By:_________________________
Rechecked by:_______________________
Signature: __________________________
Mark
Answer ALL questions.
1.The diagram below shows the mixture of particles of wax and white spirit in Wax Seal.
not to scale
After Jill sprays the car, the white spirit evaporates leaving a layer of solid wax on the surface.
(i) In the box below, draw eight circles, , to show the arrangement of particles in a gas.
And describe how particles are arranged
________________________________________
2
________________________________________
(ii) In the box below, draw eight circles to show the arrangement of particles in a solid.
And describe how particles are arranged
________________________________________
________________________________________
Maximum marks 4
2/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
2
2. Sara shone a ray of light at a mirror as shown below.
She measured the angle of reflection for different angles of incidence.
Her results are shown below.
1
(a) Which angle of reflection was not measured accurately?______________
i. How can you tell this from the table?
_______________________________________________________________________________
_______________________________________________________________________________
2
ii.
P
Which arrow, P, Q, R or S, shows the reflected ray?
Q
......................
R
1
S
mirror
lamp
3/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
(b) James set up a different experiment as shown below
He measured the angle of refraction for different angles of incidence.
His results are shown in the graph.
Use the graph to answer the questions below.
(i) When the angle of refraction is 20º, what is the angle of incidence?
_______________________º
1
(ii) What conclusion could James draw from his graph? _______________________________
Complete the sentence below.
When light passes from air into glass, the angle of incidence is always___________________
the angle of refraction.
(c) On diagram 2, above the page, draw a line to continue the refracted ray as it leaves the glass
block.
1
4/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
1
3a. Arhum made two electromagnets as shown below.
He used paper-clips to test the strength of each electromagnet.
He switched on the power supply in both circuits.
(a). How can you tell that the strength of both electromagnets is the same?
________________________________________________________________________
________________________________________________________________________
1
(b) .David switched off the power supply in both circuits.
The paper-clips fell off the iron core, but not off the steel core.
Why is iron used, rather than steel, for the core of an electromagnet?
Use the diagrams above to help you.
_________________________________________________________________________
1
-_________________________________________________________________________
maximum 2 marks
5/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
3b.
The list below shows properties that different elements can have.
 magnetic
 can be compressed
 very high melting point
 very low melting point
 good conductor of heat
 poor conductor of heat
 good conductor of electricity
 poor conductor of electricity
(a)
Which two properties from the list above make aluminum suitable for saucepans?
1. .................................................................................................................
2. .................................................................................................................
2 marks
(b)
Which property in the list above explains why?
(i)
Copper is used in the cable of a television?
.............................................................................................................
1 mark
(ii)
a lot of oxygen gas can be pumped into a very small container?
.............................................................................................................
1 mark
Maximum 4 marks
6/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
4.The chemical formulae for four acids are shown in the table below.
(i) Give the name of the element that is present in all four acids.
1
________________________________________________________________________
(ii) Give the names of the two other elements present in sulphuric acid.
1._________________________________-
2
2._________________________________
(iii) How many atoms are there in the formula HNO3 (nitric acid)?
1
_______________________________________
Maximum marks4
5.Draw a line from each of the substances below to the group that it belongs to.
Draw only three lines.
3
Maximum marks 3
7/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
6. Hannah has three rods (A, B and C) made from different metals.
One rod is a magnet; one is made of copper; and one is made of iron.
She does not know which rod is which.
Each rod has a dot at one end.
(a) Hannah uses only a bar magnet to identify each rod.
She puts each pole of the bar magnet next to the dotted end of each rod.
Complete Hannah’s observations in the table below.
Write if each rod is copper, iron or a magnet.
4
Repel
Maximum marks 4
8/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
7. (a) The drawings below show that different elements are used for different objects.
Draw a line from each element to the reason for using that element.
Draw only four lines.
element used
reason for using the element
It is lighter than air.
copper
for the base
of a
saucepan
It is a good conductor of heat.
gold
for a ring
It is a good conductor of
electricity.
14
4
helium
in a balloon
today
It stays shiny because it does
not react with oxygen.
°C 110
10
0
90
80
70
60
50
40
30
20
10
mercury
in a
thermometer
0
–1
0
It is a liquid at room
temperature.
4 marks
9/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
8. Write the formula of the formula of following compounds by using table given below.
Group in Periodic Table
1
2
3
4
5
6
7
Valency
1
2
3
4
3
2
1
H
Li
Na
Be
Mg
Ca
B
Al
C
Si
N
P
O
S
F
Cl
Br
Examples
1
i. Sodim Chloride
1
ii. Calcium Bromide
iii. Aluminium oxide
1
iv. Carbon di oxide
1
b. Complete the following equations
v. Lead + Oxygen
vi. copper + _________________
10/12
Ms.Seema Khokhar
2
Copper oxide
Science \Year 8 \ T 3
c. Elephants keep cool by losing heat from their ears.
A
B
Predict which elephant can lose more heat from its ears.
_______________________elephant
1 mark
Give the reason for your answer.
__________________________________________________________________
1 mark
__________________________________________________________________
Maximum 8 marks
11/12
Ms.Seema Khokhar
Science \Year 8 \ T 3
10.Nicola is trying out her new roller blades. Robert is pulling her along with a rope. Arrows
A, B, C and D show the directions of four forces acting on Nicola.
a.Which arrow shows the direction of the force of gravity on Nicola?
Give the letter.
...............
1 mark
Nicola lets go of the rope and she slows down. Gravity still acts on Nicola.
b.Give the name of one other force still acting on Nicola after she lets go of the
rope.
...........................................................
1 mark
c. Is it balance or in balance force?
…………………………………………………….
1 mark
d. Which arrow shows the direction of the force of the rope on Nicola?
Give the letter.
..............
1 mark
e. What is balance force?
1 mark
………………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………………..
f. If 50N force is applying at east and 50N force is applying towards west. What will be the resultant force?
Which force it is?
50 N
1 mark
50N
Calculaton_______________________________________________________________________
Maximum marks 6
12/12
Ms.Seema Khokhar
Science \Year 8 \ T 3