kimia p3 sbp mid year spm 2008
TRANSCRIPT
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Untuk Kegunaan Pemeriksa
Soalan MarkahPenuh
MarkahDiperoleh
1 18
2 15
3 17
JUMLAH 50
Nama : ... Kelas : ...
SEKTOR SEKOLAH BERASRAMA PENUHKEMENTERIAN PELAJARAN MALAYSIA
_______________________________________________
PEPERIKSAAN PERTENGAHAN TAHUN
2008
KIMIA
KERTAS 3
Satu jam Tiga Puluh Minit
JANGAN BUKA KERTAS SOALAN INI SEHINGGA DIBERITAHU
1. Tuliskan nama dan tingkatan pada
ruang yang disediakan.2. Calon dikehendaki membaca maklumat
di halaman 2.
Kertas soalan ini mengandungi 9 halaman bercetak
4541/3KimiaKertas 3Mei20081 Jam
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INFORMATION FOR CANDIDATES
1. This question paper consists of three questions. Answer all questions.
2. Write your answers for Question 1 and Question 2 in the spaces provided in the question
paper..3. Show your working. It may help you to get marks.
4. If you wish to cancel any answer, neatly cross out the answer.
5. The diagrams in the questions are not drawn to scale unless stated.
6. Marks allocated for each question or part question are shown in brackets.
7. The time suggested to answer Question 1 and Question 2 is 45 minutes and Question 3 is
45 minutes .
8. You may use a non-programmable scientific calculator.
9. Hand in this question paper at the end of the examination.
Marks awarded:Mark Description
3 Excellent : The best response
2 Satisfactory : An average response
1 Weak : An inaccurate response
0 No response or wrong response
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1. An experiment was conducted to find out the effect of temperature on the rate of reaction.
50 cm 3 of sodium thiosulphate solution 0.2 mol dm -3 at 30 oC was put into a 150 cm 3
conical flask. Then the conical flask was placed on an X sign on a piece of white paper.
5 cm 3 of sulphuric acid 1.0 mol dm -3 was added to the sodium thiosulphate solution and
shaken. At the same time, the stop watch was started. The stop watch was stopped as
soon as the X sign was no longer visible. The same steps of the experiment were
repeated for sodium thiosulphate solution which was heated to 35 oC, 40 oC, 45 oC and
50oC.
Diagram 1 shows the reading of the stop watch for each of the reaction at different
temperatures.
(a) Record the time for each reaction in the spaces provided in Diagram 1.
[3 marks]
Time , t 1
at 30o
CTime , t 2 at 35 o C
Time , t 3 at 40 o C
Time , t 4 at 45 o C Time , t 5
at 50 o C
Diagram 1
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(b) State one observation in this experiment.
[3 marks]
(c) Construct a table and record temperature, time, and 1/ time for this experiment.
[3 marks]
(d) (i) Plot a graph of temperature of sodium thiosulphate solutions against 1/ time.[3 marks]
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Graph of temperature against 1/ time
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(ii) Based on the graph in (d) (i), state the relationship between the rate of reactionand temperature.
.
[3 marks]
(e) Complete the Table 1.1 based on the above experiment.
Type of variable Action that needs to be taken
(i) Manipulated variable:
.
.
.
The way to manipulate the variable:
...
...
...
(ii) Responding variable:
.
.
.
What to observe in the responding variable:
...
...
...
(iii) Fixed variable:
.
..
The way to maintain the fixed variable:
...
......
[3 marks]Table 1.1
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2. The pupil carried out an experiment to construct the electrochemical series of metalsusing 0.5 mol dm -3 copper(II) sulphate solution as the electrolyte.
The set up of apparatus of this experiment is shown in Diagram 2.
Diagram 2
Table 2 shows the voltmeter readings of each cell that obtained from the pairs of metals.
Experiment Pair of metals Reading of voltmeter
( V )Y electrode Positive electrode
I Magnesium Copper 2.70
II Iron Copper 0.78
III Zinc Copper 1.10
IV Lead Copper 0.45
Table 2
(a) Based on experiment I,
(i) Write the overall ionic equation.
[ 3 marks ]
Copper(II) sulphate solution
YCu
V
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(ii) Based on the change in size that you observed at the magnesium electrode after30 minutes, state the inference.
[ 3 marks ]
(b) Predict the voltmeter readings of the cell when zinc and lead metals are used.
[ 3 marks ]
(c) Based on Table 2, arrange the metals zinc, iron, magnesium, lead and copperin an ascending order based of their tendency to release electron.
[ 3 marks ]
(d) Give the operational definition of the above reaction.
[ 3 marks ]
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3. Diagram 3 shows two beakers containing colourless solution labelled A and B.
Diagram 3
You are told that the two colourless solutions are calcium nitrate and magnesium nitrate. You are
required to label correctly the name of each solution in the containers.
Design an experiment to identify which is calcium nitrate and which is magnesium nitrate
solution by using aqueous of ammonia solution as a reagent.
Your answer should include the following:
(a) Problem statement(b) Hypothesis
(c) All variables
(d) List of materials and apparatus
(e) Procedure
(f) Tabulation of data
[17 marks]
END OF QUESTION PAPER
Beaker A Beaker B
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SULIT 4541/1/2/34541ChemistryMarking SchemeMei
2008
BAHAGIAN SEKOLAHKEMENTERIAN PELAJARAN MALAYSIA
______________________________________________PEPERIKSAAN PERTENGAHAN TAHUN 2008
FORM 5 CHEMISTRY
MARKING SCHEME FOR PAPER 1, 2 AND PAPER 3
Peraturan pemarkahan ini mengandungi halaman bercetak.
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PAPER 1
1 B 21 D 41 D2 C 22 D 42 B
3 B 23 B 43 D4 C 24 A 44 C5 D 25 C 45 B6 A 26 A 46 A7 B 27 D 47 B8 A 28 A 48 D9 D 29 C 49 C
10 D 30 A 50 B11 D 31 A12 C 32 B
13 A 33 D14 A 34 A15 C 35 C16 B 36 A17 C 37 D18 C 38 B19 C 39 B20 C 40 D
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PAPER 2-SECTION A
No. Rubric Mark
1 a
b (i)
(ii)
c
d
e (i)
(ii)
(iii)
GHas stable /octet electron arrangement//8 valence electron
2A + 2H 2O 2AOH + H 2
Use a small pieces//use a forcep// use a google
G,E,D, A,J,L
Has same valence electron// valence electron is 1
DE 2 r : E2D
[can draw the diagram of electron arrangement correctly]
- Correct structure of atoms
- Correct ratio of atoms=1:2
Has (neutral ) molecule
TOTAL
11
1
1
1
1
1
2
1
10
2 a
b(i)
(ii)
c
d
e (i)
(ii)
(iii)
T1
PQ: solid + liquid
RS: liquid
Heat energy absorbed
is used to overcome the forces of attraction between particles
// Heat is absorbed to overcome the intermolecular forces
r: ion/atom
(1+1)
The particles / molecules move faster
Iodine/I 2 //napthalene/C 10H8
Copper/ Cu
Ion
Diffusion
TOTAL
1
1
1
1
1
1
1
1
1
1
10
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3 a (i)
(ii)
b (i)
(ii)
(iii)
c (i)
(ii)
d
3H 2 + N 2 2NH 3
( Extract from ) air
Neutralization
H2SO 4+ 2NH 3 (NH 4)2SO 4
//H2SO 4+ 2NH 4OH (NH 4)2SO 4 + H2O
Fertilizer
Tin
In pure copper the layer of atom are easily slide over each
other when external force is applied on them.
The different size of foreign atoms in allloy are prevent the
layers of atom from slide each other when external force is
applied.
TOTAL
1
1
1
1
1
1
(1+1)
1
1
10
4 a
b(i)
(ii)
1 Diagram of set up of apparatus complete and functional
2 Label
(Anode) impure copper and (cathode ) pure copper
3 ( Electrolyte) copper (II) sulphate / copper (II) chloride // copper
(II) nitrate solution
a: chemical formula
1 become thinner // decrease in mass
2 become thicker // increase in mass
1 ( Remain )unchanged
2 Number of Cu 2+ ions produced at anode same as number of
copper atoms produced at cathode // the rate of formation of Cu 2+
1
1
1
1
1
1
Copper atomCopper atom
Tin atom
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c (i)(ii)
d
ions at the anode is the same as the rate of discharge of Cu 2+ at
cathode.
(Anode ):Cu Cu 2+ + 2e
(Cathode ): Cu 2+ + 2e Cu
Electroplating of metals/ Extraction of reactive metals
TOTAL
1
1
1
1
10
5 a
b
c (i)
(ii)
d
2H 2O2 O2 + 2H 2O
Number of mole of H 2O2 = 20 x 2/1000= 0.04
2 mol of H 2O2 produce 1 mol of O 2 //
Number of mole of O 2 = 0.04/2 = 0.02
Volume, O 2 = 0.2 x 24dm 3 = 4.8 dm 3
Rate of reaction in experiment II is higher than experiment I
The concentration/number of molecule per unit volumeof
hydrogen peroxide in II is higher
The frequency of collision between H 2O2 molecule is higher
The frequency of effective collision is higher
Volume of gas/cm 3
Time(s)
Label Y axes and X axesCorrect curve and label I and II
TOTAL
1
1
1
1
1
1
1
1
11
10
II
I
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6 a
b (i)
(ii)
(iii)
c (i)
(ii)
(iii)
d (i)
(ii)
(iii)
A compound that contain element of carbon and derive from living
organisms.
C2H4
ethene
double bond between carbon atoms
(a: C=C )
Acidified potassium manganat (VII) // Acidified potassium
dicromate (VI)
Oxidation
Purple to colourless // orange to green
C2H4 + H 2O C2H5OH
Alcohol
Temperature 300 oC // Pressure 60 atmosphere // concentrated
phosphoric acid
TOTAL
1
1
1
1
1
1
1
1
1
1
10
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SECTION B
No. Rubric Mark
7 a (i)
(ii)
b
Compound that form when non metal atom gain/receive/accept
electron that release/lose/donate by metal atom to achieve stable
/octet/duplet electron arrangemen
Compound that form between non metal atom by sharing their
valence electron to achieve stable/octet /duplet electron
arrangement
Between P and Q
Atom X has 1 valence electron
Atom X loses/donates/transfers 1 electrons to form X + ion //
X X+ + e- and attain stable octet electron arrangement
Atom Y has 7 valence electrons
Atom gains/receives/accept 1 electron to formY - ion//
Y + e- Y-
attain the stable /octet electron arrangement
The two oppositely-charged ions// the X + and Y - ion are
bonded together by a strong electrostatic force
To form a ionic compound with the formula XY// diagramn
Max 7
1
1
1
1
11
1
11
X
Y
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(ii)
(iii)
Between Y and Z
Atom Z has 4 valence electrons and atom Y has 1 valence
electrons
One atom Z contributes 4 electrons and (each) atom Y
contributes one electron for sharing .
Atom Z shared 4 pairs of electron with 4 atoms Y
to attain a octet /stable electron arrangement respectively
diagram
Magnesium oxide is an ionic compounds
Strong electrostatic force of attraction exists between
Mg 2+ and O 2 - //
the oppositely-charged magnesium ions and oxide ions in
Magnesium oxide are held together by strong ionic bonds
A lot of heat energy // high of energy is required to break the
strong forces
Tetrachloromethane is a covalent compound
Weak intermolecular forces //held together by weak (Van der
Waals) force of attractions between molecule
little heat energy //low energy is needed to overcome the
weak forces
1
1
111
1
1
1
1
1
1
Z YY
Y
Y
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8 a
b
c(i)
Empirical formula- Formula shows simplest ratio of atoms of each
element in the compound
Molecular formula- Formula shows actual number of atoms of
each element in the compound
Molecular Formula = ( Empirical formula )n= ( CH 2 )n
Relative Molecular Mass ( CH 2 )n = 7012n + 2n= 7014n=70
n=5
Molecular Formula C 5H10
1. Metal Z is cleaned using sand paper
2. A crucible and its lid are weighed and the mass is recoded
3. Metal Z is palced in the crucible. The crucible,lid and its
content is weighed and the mass is recorded.
4. The crucible with its content is heated strongly without
lid.
5. When metal Z start burn, the crucible is covered by its
lid
6. the covered is raise a little at intervals
7. When there is no more reaction, the lid is removed and the
crucible is heated strongly for a few minutes.
8. Cool the crucible and weigh the crucible,its lid and its
Content and record the mass.
9. The process of heating, cooling and weighing is repeated
until constant is obtained.
10. (Precaution step );
Close the crucible immediately to prevent loss of
1
1
1
11
11
1
1
1
1
1
1
1
1
TOTAL 20
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Element Z O
Mass(g) 1.30 0.32
mol 1.30/65=0.02 0.32/16=0.02
Simplestratio
1 1
Empirical Formula ZO
TOTAL
1
1
1
1
1
20
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PAPER2 SECTION C
No Rubric Mark
9 a
b (i)
(ii)
c(i)
Sample answer :Zn + HNO 3 Zn(NO 3)2 + H2O
ZnCO 3 + HNO 3 Zn(NO 3)2 + H2O + CO 2
ZnO + HNO 3 Zn(NO 3)2 + H2O
Any two
Methanoic acid partial ionizes in water
produce low concentration of hydrogen ionGlacial ethanoic acid has (neutral) molecule
Methanoic acid aqueous ionizes in water
to produce free moving ion
Procedure :
1 100 cm 3 of 0.1 moldm -3 sulphuric acid is poured into a beaker
and heated slowly.
2 zinc carbonate is added into the sulphuric acid until in excess/nolonger dissolves.
3 Stir the solution and filtered.
4 The filtrate is poured into an evaporating dish and heat untilsaturated
5 The hot saturated salt solution is allowed to cool
6 The crystals formed are filtered out, rinsed with distilled water
7 dried between sheets of filter paper.
2
1
11
1
1
1
1
1
1
1
1
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(ii)
d
ZnCO 3 + H2SO 4 ZnSO 4 + H2O + CO 2
Number of mole , H 2SO 4 = 0.1( 100 )/1000
= 0.01
1 mol of H 2SO 4 produce 1 mol of ZnSO 4
Mole of ZnSO 4 = 0.01
Mass of ZnSO 4 = 0.01 X 161
= 16.1 g
Sample answer :
1 ammonium chloride as a fertilizer2 copper (II) sulphate as a pesticide
3 hydrated calcium sulphate to make plaster casts4 sodium chloride food additiveAny 2 suitable anwers(1+1)
TOTAL
1
1
1
1
1
1
20
10a (i)
(ii)(iii)
(iv)
(v)
catalyst
esterification
CH 3COOH + C 3H7OH CH 3COOC 3H7 + H2O
Correct reactant
Correct product
Ethyl propanoate
Sweet smell/fruity smell/fragrant smell
//insoluble in water/soluble in organic solvent
//colourless //less dense than water
any two properties (1+1)
1
1
1
1
2
2
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b (i)
(ii)
Bacteria will produce lactic acid/H + ions which neutralize
negatives charge of the protein membrane/ rubber molecules
The rubber molecules will be collide with each other and
cause protein membrane brokenRubber polymer are released and lump together
Hydroxide ions/OH - from ammonia solution will neutralise
H+ produced by acid
The protein membrane remains negatively charged
The rubber particles repel each others/ the rubber polymers
cannot combine and coagulate
The presence of cross-linkage of sulphur atoms between
the rubber molecule
When vulcanized rubber is stretched and release, the cross-
linkage will pull the chain back to their original
arrangement
Diagram
Improves the elasticity and strength of the rubber / make
vulcanized rubbers more resistant to heat /organic solvent
orResistant to oxidation :
The presence of cross-linkage of sulphur atoms between
the rubber molecule
Diagram
C=C in vulcanized rubber is less than C=C in the
unvulcanized rubber,
so vulcanize rubber is more resistant to oxidation
TOTAL
1
1
1
1
1
1
1
1
1
1
1
1
1
1
20
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PAPER 3
1 (a) KK0503 Measuring and using numbersEXPLANATION SCORE
[Able to write all the times with units accurately]
Suggested answer:
t 1 55.0 s, t 2 48.0 s , t 3 42.0 s , t 4 37.0 s , t 5 33.0 s
3
[Able to record all the times accurately but without units / no decimal place]t1 55.0 , t 2 48.0 , t 3 42.0 , t 4 37.0 , t 5 33.0 // // t1 55 s , t2 48.0 s , t 3 42 s, t 4 37s, t 5 33s
2
[Able to write at least 3 readings of the times accurately] 1
No response given / wrong response 0
1 (b) KK0501- ObservationEXPLANATION SCORE
[Able to state the colour of sulphur and the rate of it is formed]Suggested answer:
Pale / light yellow precipitate is slowly formed
3
[Able to state the colour of sulphur]Pale / light yellow precipitate is formed.
2
[Able to state the formation of precipitate]
A precipitate is formed.
1
No response given / wrong response 0
1 (c) KK0506 CommunicatingEXPLANATION SCORE
[Able to construct a table correctly containing three labeled columns withcorrect units and record all the time and 1/time accurately ]
Suggested answer:
Temperature,o
C
30 35 40 45 50
Time , s 55.0 48.0 42.0 37.0 33.01 / time , s -1 0.018 0.021 0.024 0.027 0.030
3
[Able to construct a table correctly containing three labeled columns withcorrect units and record all the time and 1/time but not accurately]
2
[Able to write at least 3 readings of the times accurately] 1
No response given / wrong response 0
1 (d) (i) KK0506 Communicating
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EXPLANATION SCORE[Able to draw a graph accurately that consists of the following aspects]Suggested answer:
1. Both axes labeled and units
( Y axis - temperature , X axis 1/ time )2. All points transferred correctly3. Uniform scale, graph size covers at least half of the graph paper.4. Straight line/ best fits drawn
3
[Able to draw a graph that consists of the following aspects]1. Both axes labeled / units
( Y axis - temperature , X axis 1/ time )2. At least three points transferred correctly3. Uniform scale, graph size covers at least half of the graph paper.4. Straight line/ best fits drawn
2
[Able to draw a graph that consists of the following aspects]1. Both axes labeled and units
( Y axis - temperature , X axis 1/ time )2. Draw a line
1
No response given / wrong response 0
1(d)(ii) KK0509 To define OperationallyEXPLANATION SCORE
[Able to interpret the relationship between the rate of reaction and thetemperature of sodium thiosulphate solution from graph accurately]Suggested answer:
The rate of reaction is directly proportional to the temperature of sodiumthiosulphate solution // As the temperature of sodium thiosulphate increasesthe rate of reaction increases.
3
[Able to interpret the relationship between the rate of reaction and thetemperature of sodium thiosulphate solution from graph ]
The rate of reaction is proportional to the temperature // the temperature is
proportional to the rate of reaction // the rate of reaction increases when thetemperature increases.
2
[Able to state an idea of hypothesisThe temperature affects the rate of reaction.
1
No response given / wrong response 0
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16
30
35
40
45
50
0.015 0.020 0.025 0.030X
X
X
X
X
Temperature / o
C
1/time , s -1
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1(e) KK0510 - State variables
EXPLANATION SCORE
[Able to state three variables and three action to be taken]Suggested answer:
Variable Action to be takenManipulated:Temperature
Heat the sodium thiosulphatesolution at different temperature // Use different temperature.
Responding:Rate of reaction / time taken for Xmarks to disappear from view.
Record the time taken for X mark to disappear from view.
Controlled :Concentration and volume of H 2SO 4,concentration and volume of sodiumthiosulphate solution, size of conicalflask.
Use the same concentration andvolume of H 2SO 4 /sodiumthiosulphate solution // Use samesize conical flask.
3
[Able to state any two variables and any two action to be taken] 2
[Able to state any one variables and any one action to be taken] 1
No response given / wrong response 0
2 (a) KK0506 Communicating EXPLAINATION SCORE[Able to write the correct overall ionic equation]Suggested answer:
Mg + Cu 2+ Mg 2+ + Cu
3
Mg + CuSO 4 MgSO 4 + Cu 2Mg Mg 2+ + 2e // Cu 2+ + 2e Cu 1 No response given / wrong response 0
2(a)(i) KK 0504 Making inferenceEXPLANATION SCORE
[Able to state the correct inference]Suggested answer:
Magnesium atom releases/donate/loses electrons to produce magnesium ion // Magnesium is corrode.
3
Magnesium becomes thinner // mass of magnesium decreases 2Magnesium dissolves 1 No response given / wrong response 0
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2(b) KK 0505 - PredictingEXPLANATION SCORE
[Able to state the voltage value]
0.65 V
3
0.63 0.64 V // 0.66 0.67 V 2< 0.64 V // > 0.67 V 1 No response given / wrong response 0
2(c)KK 0508 Interpreting DataEXPLANATION SCORE
[Able to arrange the position of all metals in an ascending order based ontendency to release electrons correctly]Copper > Lead > Iron > Zinc > Magnesium
3
[Able to arrange the position of all metals in descending order based ontendency to release electrons]Magnesium > Zinc > Iron > Lead > copper
2
[Able to arrange the position of at least four metals in ascending order based on tendency to release electrons correctly]
1
No response given / wrong response 0
2(d) KK0509 Operational definitionEXPLANATION SCORE[Able to state the correct and complete operational definition]Suggested answer:
The further the metal is from copper in the electrochemical series, the greateris their voltage reading. //
3
[Able to give incomplete relationship]Suggested answer:
The further apart the metal is in the electrochemical series, the greater thepotential difference / voltage reading.
2
[Able to state an idea]Suggested answer:
The position of metal influence the voltage reading // Type of metal influence the voltage reading.
1
No response given / wrong response 0
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3.(a) KK051021 Statement of problemEXPLANATION SCORE
[Able to make a suitable statement of problem]
Suggested answer:
How to differentiate between magnesium nitrate solution and calcium nitratesolution // How to differentiate between magnesium ion and calcium ion
3
[Able to make a suitable aim]Suggested answer:
To differentiate the presence of magnesium ion and calcium ion by usingaqueous ammonia solution.
2
[Able to state an idea of statement of problem or aim] 1
No response given / wrong response 0
3(b) KK051202 Stating hypothesisEXPLANATION SCORE
[Able to state the relationship between manipulated variable and respondingvariable correctly]Suggested answer:
If the addition of aqueous ammonia solution forms white precipitate which isinsoluble in excess ammonia aqueous solution, then the solution tested is
magnesium nitrate. // If aqueous ammonia solution is added and no changeoccur then the solution tested is calcium nitrate.
3
[Able to state the relationship between manipulated variable and respondingvariable]
2
[Able to state an idea of the hypothesis] 1
No response given / wrong response 0
3 (c) KK051202 Stating variables
EXPLANATION SCORE[Able to state all the three variables correctly]Suggested answer:
Manipulated variable : magnesium nitrate and calcium nitrate // Mg 2+ and Ca 2+
Responding variable: formation of white precipitateControlled variable : aqueous ammonia solution[Able to state any two of the variables correctly]
[Able to state one of the variables correctly or state idea regarding variable]
No response given / wrong response
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3(d) KK051205 List of substances and apparatusEXPLANATION SCORE
[Able to state the list of substances and apparatus correctly and completely]
Suggested answer:
Test tube, dropper, test tube rack 0.5 mol dm -3 magnesium nitrate solution, 0.5 mol dm -3 calcium nitratesolution, aqueous ammonia solution.
3
[Able to state the list of substances and apparatus correctly but not completely]Suggested answer:
Test tube0.5 mol dm -3 magnesium nitrate solution, 0.5 mol dm -3 calcium nitratesolution, aqueous ammonia solution.
2
[Able to state an idea about the list of substances and apparatus]Suggested answer:
Test tubemagnesium nitrate, calcium nitrate
1
No response given / wrong response 0
3(e) KK051204 Technique /Precedure
EXPLANATION SCORE[Able to state a complete experimental procedure]Suggested answer:
1. 2 cm 3 of solution A is poured into a test tube.2. A few drops of aqueous ammonia solution are added into the test tube
using a dropper and the test tube is shaken well.3. If the precipitate is formed, aqueous ammonia solution is added
continuously until no further change occurred / until excess4. The mixture is shaken well.5. The changes occur is recorded in a table.6. Steps 1 to 4 are repeated using solution B.
3
[Able to state a complete experimental procedure]1,2,3,4,5
2
[Able to state a complete experimental procedure]1,2,3,5
1
No response given / wrong response 0
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8/14/2019 Kimia P3 SBP Mid Year SPM 2008
30/30
3(f) Tabulation of dataEXPLANATION SCORE
[Able to exhibit the tabulation of data correctly ]
Reagent ObservationTest tube/Solution A Test tube/Solution B
Aqueousammonia solution 3
[Able to exhibit the tabulation of data less accurately ]
Reagent Test tube /Solution A Test tube/Solution BAqueousammonia solution
2
[Able state an idea about the tabulation of data] 1
No response given / wrong response 0
END OF MARKING SCHEME