}<ENT RIDGE SECONDARY SCHOOL
SEC 1 E)(PRESS
SCIENCE
MID.YEAR EXAMINATION 201A
Section A
(}
The total mark for this section is 30
1
X is an apparatus that has three legs and can support other apparatus
while
heating. X is most likely a .... ......
A
B
C
D
2
Which of the following statements ts not correct about the use of the Bunsen
bu rner in the laboratory?
A
B
C
D
3
conical flask
measuring cylinder
tripod stand
wire gauze
Adjust the size of the air hole to control the intensity of the flame.
Close lhe air hole before igniting the burner.
Leave the air hole open fully when the Bunsen burner is not in use.
Use non-luminous flame if strong heating of a substance is required
Thomas wants to find the density of a large irreg ular-shaped stone he found in his
garden. Which of the following apparatus should he use?
Displacement can
Electronic
balance
Measuring
Metre rule
cylinder
A
B
c
o
4
The average measurement for the length of a book was calculated to be
20.865 cm. lf the measurement was taken with a pair of Vernier calipers, how
should it be recorded?
A
B
C
D
E
20 cm
20.8 cm
20.87 cm
20.865 cm
Material Z has the following properties. lt is high in density, has a high melting point
and is a good conductor of electricity. What is material Z?
A
B
C
D
Ceramic
Fibres
Glass
Metal
Science
2
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6
Mandy flattened a ball of plasticine weighing 250 g using her hands. Which of the
following statements about the plasticine is true?
B
c
D
7
Density
Mass
Decreased
Decreased
Remains the same
Remains the same
A
Decreased
lncreased
Decreased
Remains the same
An object K floats in liquid S but sinks in liquid T, as shown in the diagrams below.
\A/hich of the following statements is correct?
liquid T
liquid S
A
B
C
D
8
Liquid S is denser than liquid T.
Liquid S is less dense than liquid T.
Liquid S is less dense than object K.
Object K is less dense than liquid T.
The diagram shows a material with dimensions 4.0 cm x 5.0 cm x 2.0 cm. lt has a
mass of 100 g.
5.0 cm
2.0 crn
4
\Mat
cm
is the density of the material?
A 0.40 g / cm3
B 2.59/cm3
C 5.09 /cm3
D 10.09/ cm3
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Science
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l8
Four students used the following ways to dissolve a sugar cube in water quickly.
Wrich is not the correct way to speed up the dissolving process?
A
B
Stir continuously
c
Crush the sugar
cube into small
pieces with a spoon
D
lce
Lower the
temperature of
water by adding ice
19
lncrease
lemperature of
water by heating
A tea strainer removes tea leaves from tea.
ft.r
--?'
Vvhich method of separation does it use?
A Chromatography
B Distillation
C Evaporation
D Filtration
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Science
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20
ldentify parts P and Q correctly in the setup shown.
P
a
A
B
c
D
21
P
o
beaker
filter funnel
filter funnel
measuring cylinder
distillating flask
filter paper
distillating flask
filter paper
The colourings of five different sweets P, Q, R, S and T were analysed using
chromatography. The final results are shown below.
Solvent line
I
ll
lrr
tt
llt
--x--X--i--X--x-PQRST
Starting line
Which of the two colourings could be mixed together to make T?
A
B
C
D
22
PandR
PandS
QandS
RandS
A mixture produces a residue when it is filtered. \Ir/hich of the following statements
about the nature of this mixture is correct?
A lt contains two solutions.
B lt does not allow light to pass through"
C lt does not have particles settling after being left for a period of time.
D
lt is a homogeneous mixture.
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23
Pure water is needed for a car battery.
Which apparatus is the best for making river water suitable for use in a car battery?
B
A
flve r
water
nver
,
water
u"trl"t
a';;i]
r
oI lce
t
heat
c
D
river
waler
nver
water
t
heat
24
The diagram shows an experimental setup
I
water out
,lask
hlus ink
rraGl ln
I
heat
I
/
bgakor
The mixture above was heated to 100oC for 3 hours. Vvhat are the colours of the
liquids in the flask and the beaker at the end ofthe experiment?
A
B
c
o
flask
beaker
blue
blue
colourless
coloudess
blue
colourless
blue
c.olourless
8
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Science
Mid-Year Examination 2018
25
\Mich of the following is not typically used in the classification of living things?
A Body colour of an animal
B Body structure ofan animal
C Flowering or non-flowering plant
D
26
Wth or without a backbone
What can a dichotomous key be used for?
I
ll
lll
To classify living organisms
To identiff living organisms
To distinguish living from non-living things
A I only
B ll only
C landll
D
l, ll and lll
Study the following flgure to answer Questions 27 and 28
Animals without
a backbone
aB-"th",r"^sl
lungs
Breathe using
g
I
Two legs
I
27
tw,th
Four legs
Iilr
I
"h"rll
l
ills
without
shelL
IV
Which of the following best represents a chameleon?
AI
Bil
cilt
DIV
28
\r'Uhich of the following refers
to mammals?
A landll
B land lll
C ll and lll
D ll and lV
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29
Wrich of the following is not a way by which animals and plants become
endangered?
A Disease
B Habitat loss
C Hunting
D Reproduction
30
Which statement(s) about bacteria is/are correct?
I
ll
All bacteria are harmful.
They are classified as antmals.
lll They may be found in the human body.
lV There are different kinds of bacteria in different shapes.
A
B
C
D
land ll
ll and lll
lll and lV
l, ll and lV
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Science
Mid-Year Examination 201 I
Section B
The total mark for this section ls 40.
I
Draw the cross-sectional diagram of the following lab apparatus.
(b) Conical flask
(a) Measuring cylinder
2
Complete the following conversions.
(a)
t4t
0.85 m =
cm
(b) 187 ml =
(c) 550 mg =
(d)
cm3
kg
0.87 L =
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tzt
ml
11
Science
Mid-Year Examination 201 8
12
3
The diagram shows a vernier calipers. lt is used to measure the dimensions
of a test-tube.
o
R
_rl
trl.lr
P
Using the alphabets (P, Q or R), identify which part needs to be used to
measure the:
(a) (i)
(
(b)
ii)
lnternal diameter
t1I
Depth
tl
l
Michael measured the diameter of a coin using the vernier calipers.
Fig 3.1 shows the jaws of the vernier calipers when they are fully closed.
Fig 3.2 shows the measurement of the coin which was made using the
same vernier calipers.
0
,|
1
2
ilil1ttil1-
t
IrTnTrnrl
5
0
l0
0
Fig 3.2
Fig 3.1
(i)
't0
5
lndicate the value of the zero error as shown in this vernier
Zerc efiot
calipers.
t11
=
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Science
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1a
(iD
Calculate the corrected diameter of the coin in the space
provided.
t3l
Corrected diameter of coin =
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Science
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4
A glass piece is dropped into a jar containing three liquids as shown
below.
It floats in mercury and gold but sinks in water.
l
Glass Piece
(a)
Define density.
t11
(b) (i)
(ii)
(c)
Label in the diagram above where water should be
located.
t1I
Label in the diagram above where mercury and gold should be [1]
located given that the density of mercury is '13.6 g/cm3 and that
of gold is 19.6 g/cm3,
Kelly wanted to make the cube float further up in the beaker. She added
about 200 g of solid L. Suggest what solid L could be.
t11
(d)
lf another material is placed in the filled beaker and it floats to the top, what
conclusion can be made about the density of this new material?
t11
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Science
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5
The table below shows some of the physical properties of four elements, A, B, C
and D.
A
Meltinq point (oC)
-272
B
'1083
c
0
-72
Element
D
(a)
(b)
Boilinq point (oC)
-269
2582
100
DensiW (q/cm3)
0.00018
eo
1.00
0.53
(o
Draw a table with suitable headings to classity these elements into
metals and non-metals based on the information in the table.
t3l
The diagram below shows part of the Periodic Table.
ll tv v vl \.'t
tl
0
l
P
# I
T
R
IIIIIII
(i)
0
S
Which elements are mosl likely to be good conductors of electricity in
the solid state?
111
(ii)
Which elements are poor conductors of heat?
....111
(iii)
Which elements have similar chemical properties?
t11
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'16
Science
Mid-Year Examination 201 8
5
lnformation of four different solid substances, W, X, Y, and Z is given below.
w
Soluble in
water
Soluble in
alcohol
Attracted to
maqnet
z
x
No
No
Yes
Yes
No
No
No
No
No
Yes
Does not
decompose
Decomposes
Does not
decompose
Does not
decompose
Yes
I
Yes
I
Effects of heat
(a) A series of separation techniques are used to separate each of the [3]
substances W, X, Y and Z from its mixture. Four separation techniques are
listed below.
filtration
evaporation
paper chromatography
magnetic attraction
Complete the flow chart by filling in the blanks with suitable separation
techniques. The same separation technique may be used more than
once.
Substances W, X, Y, Z
(r,
SubstanDE Z
Substances W. X, Y
Add lsaler lollov{ed by
(iii
Sutrslance W + water
Substances X, Y
Add alcohol follouretJ lry (iii)
Substance X + alcohol
Substance Y
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Science
Mid-Year Examination 20'1 8
(b)
To obtain pure and dry samples of substance W, Alex
performed
evaporation to dryness to the mixture obtained in (a)(ii). He decided to
use the same method to obtain pure dry samples of substance X as well.
Suggest a reason why it is unwise to do the same for substance X.
t11
7
\Nhen a teabag is dipped in water, the tea grains start to diffuse throughout the
water.
water
tea bag
tu_.J
tea grains diffi,rse
\
out of the bag
after a while...
(a)
tiny particles settled at
the bottom ofwater
Which evidence from the diagram shown above indicate that the mixture is a
suspension?
tll
(b)
State two other tests you would perform and the expected results to confirm
that the mixture is a suspension.
(i)
Test
1
:
tll
Expected result:
t11
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'18
Science
Mid-Year Examination 201 8
(
ii)
Test 2:
11l
Expected result:
.
I (a) The table below shows characteristics
Name of leaf
Are the
leaves
pointed?
of four plants.
Are the leaf
edges
smooth?
Are the
veins
parallel?
Are the
leaves
narrow?
Grass
Water
spinach
Balsam
Papaya
I
Using the information, construct a dichotomous key
You do not need to use all the characteristics in the
to identify the leaves.
table.
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19
t3l
Science
Mid-Year Examination 2018
(b) (i)
Living things depend on each other for survival. One example is the
relationship between humans and cows. State one reason why humans
depend on cows.
t1l
However, human activities are resulting in living things becoming 'endangered'
and'elitinct'.
(ii)
\r'/hat is the difference between the lerms 'endangered' and 'extinct'?
t2t
(iii)
Suggest two ways humans can slow down the rate
getting endangered.
of living
things
t2I
End of Booklet 'l
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Science
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Section
C
The total mark for this section is 30.
questions from this section.
Answer
The last question is in the form of Either / Or and only one question should be attempted.
!@
r
(a)
Vanillin is a common flavouring agent that can be extracted from Vanilla
beans. lt is one of the most important aromatic flavor used in foods, beverages
and perfumes. Due to its wide usage, it is produced on a scale of more than
10,000 tonnes per year by chemical industries. Vanillin is soluble in water and
its composition is as shown below.
Oxygen
32V"
Carbon
62v"
Hydrogan
6%
(i)
Based on the information given, state
if
Vanillin
is
an element,
compound or mixture. Explain your answer.
t2l
(ii)
A tablespoon of Vanillin was added to a beaker of water. Predict what
would be observed if this mixture was filtered and how did this happen?
t2t
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Science
Mid-Year Examination 201 8
(iii)
lf Vanillin was accidentally mixed with some iron filings, describe how
you would separate the mixture of Vanillin and iron.
tzt
(b)
The figure below shows a beaker containing lumps of table salt about to be
dissolved in water.
aaaa
(i)
John is investigating the factors that affect the rate of dissolving. State
three methods he could use to make the table salt dissolve faster in the
water.
t31
(ii)
After all the table salt had dissolved, John added another 20 g of table
satt to the mixture. However. the salt could not be dissolved.
\\hy was this
so?
..
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zc
t1l
Science
Mid-Year Examination 201 I
2 (a)
A purple food colouring solution was analysed using paper chromatography.
Fig 2.'l and Fig 2.2 show two different paper chromatograms, with different
solvents being used.
solvent
cork
cork
fron t
boiling
1."
o-
tube
o--
starting
o-
line
light red
dark red
blue
t____-
solvent Y
{.i:=
solvent Z
Fig2-2
Fig2-1
(i)
Explain why the starting line should be drawn in pencil.
t11
(ii)
Compare Fig 2.1 and Fig 2.2. State which of the following solvent
(Y or Z) is the purple food colouring not soluble in. Explain your
answer.
t21
(iii)
State whether the purple food colouring is
a pure substance or a
mixture. Explain your answer.
tzl
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Science
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(b)
The figure below shows a distillation setup.
thermometer
water out
I
/
l]
/-x
tl
/
!va ter in
porcelain
chips
round-bottom flask
heat
(i)
Name X and explain why it must be positioned tilted downwards.
t2t
(ii)
Name Y and explain one difference between the original liquid and the
distillate.
lzt
(iii)
What is the purpose of using the porcelain chips?
t11
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25
Science
Mid-Year Examination 201 8
3
EITHER (Circle Q 3E on cover page of Booklet 2)
Jess wants to test if distilled water or sea water evaporates faster. She is given two
beakers containing '100 cm3 of each type of water. The beaker containing 100 cm3 of
distilled water is labelled B'l while the other beaker of sea water is labelled 82.
-l
:
I
I
I
B1
82
(distilled wate0
(seawater)
Design an experiment to investigate which type of water evaporates faster.
(a) Suggest a possible hypothesis for this experiment.
.........111
(b)
State two variables to be kept constant.
.....
(c)
t21
State the variable to be measured.
t11
(d)
Describe briefly the steps to be carried out in this experiment.
...... .t31
6
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Science
Mid-Year Examination 201 8
(e)
(f)
Present a table with proper headings that you would use to record your results.
You do not need to include any results.
l2l
Jess wants to change the experiment setup to test if the temperature of water
will affect its rate of evaporation. State one change she should make to the
setup.
tll
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Science
Mid-Year Examination 201 8
3
OR (Circle Q 30 on cover page of Booklet 2)
(a)
Match the organisms below with the benefits they give to humans and nature.
t4I
Organisms
Benefits
Birds
Rich source of protein for
humans
Fish
Break down rotting matter
Trees
Provide raw materials for
making furniture
Bacteria
Control the number of
pests feeding on crops
(b) lt is common practice for people who can no longer take care of their pet turtles
to release them into ponds and reservoirs. Explain two reasons why this is not
the right thing to do.
t2t
Farmer Tan realised his crops were affected by the presence of a pest. He built
birdhouses near his farm to attract birds to nest so that they would feed on the pest at
the same time.
(c) (i)
Predict what would occur if many new kinds of birds bred in the birdhouse
. I1l
I
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Science
Mid-Year Examination 201 8
(ii)
Another farmer had the same pest problem. However, to solve it, he
planted a new kind of crop that was resistant to the pests. What are the
possible threats to the diversity in the area?
t11
(d)
Briefly describe two activities that have harmful effects on the
environment.
.
t21
End of Booklet 2
I
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Science
Mid-Year Examination 2018
CONFIDENTIAL
For ofFoal t.lse on y
KENT RIDGE SECONDARY SCHOOL
SEC 1 EXPRESS
SCIENCE
MID-YEAR EXAMINATION 2018
MARKING SCHEME
SECTION
A
(30 marks)
Answer
Question
Answer
c
c
16
B
17
B
3
A
18
c
4
c
19
D
5
D
20
B
6
D
21
G
7
A
22
B
o
B
z3
A
o
c
24
B
10
D
Z5
A
11
c
It)
D
12
A
1.)
D
lo
A
14
A
29
D
15
A
30
c
Question
1
Setter
I\4s
Kalpana Kaleselvan
B
1
CONFIDENTIAL
For oFf cial Llse Only
SECTION
B
(40 marks)
1
Mark
Awarded
Marking Point
Qn
it
(a)
Rema rks
1
t
Lr
(b)
1
\
I
2
.,
(a)
85
1
(b)
187
1
(c)
0.00055
1
(d)
870
1
(i)
o
1
(ii)
R
1
(i)
+ 0.03 cm
1
(a)
(b)
Reject: lf unit is not provided or'+'sign is
m iss
(
ii)
ing.
1.06 - (+0.03)
1-
= 1.06 - 0.03
correct
answer for
Fig 3.2
= 1 .03 cm
Allow ECF from (bXi).
Reject: lf unit is not provided.
1correct
working
1final
answer
2
Setter Ms Kalpana Kaleselvan
32
CONFIDENTIAL
4
Density is mass Der unit volume.
(a)
(b)
1
,|
(i)
Glass Piece
(
I
water
't-
ii)
for 2
I
Glass Piece
correct
answers
merEury
gotd
(c)
Salt
1
(d)
It is the least dense of all the materials in the
1
beaker. or
It is less dense than water.
(if part (bXi) was answered correc,tly)
5
1-
(a)
Metab
llon-met.ls
B
A.C,D
clear
headings
1correct
metals
1correct
non-metals
(b)
QandT
1
P,RandS
1
(iii)
QandT
1
(i)
Magnetic attraction
1
(ii)
Filtration
1
Filtration
1
(i)
(
6
(a)
(
ii)
iii)
Setter: Ms Kalpana Kaleselvan
I
3
CONFIDENTIAL
For Officral Use Only
Alcohol is flammable
(b)
1
or
X will decompose when heated
7
Tea grains are insoluble in water.
(a)
1
or
Tiny particles settled at bottom of water
(b)
(i)
Test
'1
:
$iq!.!g[!
1
thro ugh the solution
1
Expected result:
Little or no liqht can pass through.
(ii)
Test 2:
Filter the mixture
1
1
Expected result:
Residues are found on the
I
(a)
lillgrjgpgl.
Accept any reasonable answer
Total: 3
1l
Sm.crr edges
RrLrqh eCges
I
a',,Fi,'*L ," """
f!tr*;-l
..i
aeai rs
Ptra el
Accurate
main
heading
(i.e. plants
/ leaves)
na(o\Y
w..,". fe,t'".
I rpinach
1Accurate
subheadings
(e.9.
smooth /
rough
edges)
Setter
l\4s
Kalpana Kaleselvan
4
CONFIDENTIAL
For Offrclal Use Only
1Specific
pla nts
accurately
classified
(e.9. g rass,
balsam)
(i)
(b)
(ii)
Accept any reasonable answer
- Leather
- Food / Beef
- Milk
'Endangered'
Living things that are at risk of extinction
1
1
'Extinct'
Living things no longer exist.
1
Accept any reasonable answer
2
Making laws to protect species
(e.9. selling elephant ivory is banned,
catching or killing orang utans in lndonesia is
illegal)
l.,l
I
Protect habitats
(e.9. Singapore and many other countries
have nature parks and reserves where
wildlife can be protected)
Breed endangered species in zoos
Raise awareness of conservation issues by
joining organisations that work to protect
wildlife
(e..9 World Wildlife Fund: WWF)
Setter Ms Kalpana Kaleselvan
CONFIDENTIAL
For Official Use Only
SECTION
C
(30 marks)
Marking Point
Qn
(a)
1
(i)
Mark
Awarded
Compound
Remarks
1
is made up of hvdrooen. carbon and
oxyqen (elementsl i n a fixed composition /
Vanillin
1
proportion
(
ii)
No resrdue would be observed on the filter paper
1
Vanillin had dissolved in the water. /
Vanill n is soluble in water
1
I
(iii)
1
. Add
water to the mixture and stir well
2. Filter the mixture and collect the
iron fillin
S
from the filtrate (Vanillin).
1-
residue for each
correct
step
or
1. Place a Egglq! over the solad mixture.
2. The iron fillinqs would be attracted to
Total: 2
the
magnet and leaving behind the vanillin powder
(b)
(i)
1. Use hot water / Boil the water to increase its
temperature.
1
2. Stir the mixture
1
3. Use crushed table salt instead of lumps. / Use
table salt with a larger exposed surface area.
1
I
2
(a)
(ii)
The solution was saturated
(i)
lf ink is used, it will
affect the accuracy of the results.
(ii)
Solvent Y
g[g!giq!@]yen!
1
and
1
1
The ink sample remains on the startinq line
1
or
The ink sample did not dissolve / is not soluble in
the solvent.
SetteI Ms Kalpana Kaleselvan
6
36
For
CONFIDENTIAL
otfloal Use Only
Mark
Awarded
Marking Point
Qn
Mixture
(iii)
Sample B ts separated out into
comDonents on the chromatogram
(b)
Remarks
3
different
X: Condenser.
(i)
1
It must be positioned tilted downwards to allow the
1
ldistillate / liouid to flow downwards easilv into
the beaker.
(Accept this answer even if the name is wrong.)
I
I
(ii)
Y. Distillate
T
1
he qrts! m!_L@iC.j9-i!0.p-We while the
1
distillate is
pure
(Accept this answer even if the name is wrong.)
(iii)
3E
(a)
(b)
It is to ensure smooth boilino of the liquid
1
Accept any reasonable answer.
Distilled water / Seawater will evaporate faster
1
Accept any 2 correct answers.
-
Temoerature of water.
Place where the two water samples
are kept.
I
Volume of water used
(c)
Volume of water left (at the end of the experiment)
(d)
1) Measure 100 c mlqfuljg[lld-rrglet
usinq a measurinq cvlinder and pour
it into a beaker, label it B1
Do the same for seawater and label the
beaker 82.
.
2)
t'
Sefter fvls Kalpana Kaleselvan
1
1Measuring
of volume
of liquids
and
differentiati
ng both
beakers
7
For
olf
CONFIDENTIAL
c al Llse On y
Marking Point
Qn
3)
4)
5)
I
Mark
Awarded
Place the two samples at the same
place / location.
Observe the water level in each beaker
after 1 dav.
Record / Measure volume of
remaininq water (using a measuring
cylinder).
Remarks
1Beakers in
same
location
and
mention of
time period
for which
expt will
last.
1Measuring
Recording
of volume
of
remainrng
water
(No need
to mention
apparatus
used )
(e)
1-
Accept any reasonable table.
Beaker
Volume of
water at the
start of the
experiment /
cm3
Volume of
water at the
end of the
experiment
/ cm3
Volume of
water that
evaporated
/ cm3
clear
headings
1appropriate
un its
B1
82
(f)
Both beakers should have water of different
1
8
Setter: lvls Kalpana Kaleselvan
38
CONFIDENTIAL
For Off c al tlsc On y
temperature.
or
Both beakers should have either distilled water or
seawater.
30
(a)
Organisms
Benefits
Birds
Rich
source of
protein for
humans
Fish
Break
down
rotting
matter
4
I
I
(b)
Trees
Provide
raw
materials
for making
fur nitu re
Bacteria
Conlrol the
number of
pests
feeding on
crops
Accept any reasonable answer
I olal.
2
The turtles mav not be able to survive in the new
environment.
The turtles mav disrupt the balance in the new
environment.
(c)
(i)
(
Setter
l\4s
ii)
There would be competition for food
The new crop would outcompete the old crop for
space and nutrients and might cause the old crop to
die out.
Kalpana Kaleselvan
1
1
I
For OlfL.
CONFIDENTIAL
rl tlce Onlv
(d)
Accept any reasonable answer.
Total: 2
Examples
Deforestation causes loss
and plants.
of habitats for animals
lntroduction of invasive species causes competition
among animals and plants and affects the balance
in the ecosystem.
10
Setter: Ms Kalpana Kaleselvan
40