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  • 7/31/2019 Chemist Marking Scheme (Main)1

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    BAHAGIAN KURIKULUM TEKNIK DAN VOKASIONAL

    KEMENTERIAN PELAJARAN MALAYSIA

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    BENGKEL

    PEMBINAAN MODUL

    PECUTAN AKHIR SPM2009

    CHEMISTRYCHEMISTRY

    MARKING SCHEMEMARKING SCHEME

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    BAHAGIAN KURIKULUM TEKNIK DAN VOKASIONAL

    KEMENTERIAN PELAJARAN MALAYSIA

    OBJECTIVE QUESTION

    1 C2 D

    3 A

    4 B

    5 A

    6 A

    7 B

    8 C

    9 C

    10 A

    11 D

    12 B

    13 D

    14 C

    15 D

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    MODULE 1MODULE 1

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    BAHAGIAN KURIKULUM TEKNIK DAN VOKASIONAL

    KEMENTERIAN PELAJARAN MALAYSIA

    PAPER 2

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    1. The table 1 shows the proton number of P, Q, R ,S and T . Based on the table answer thefollowing questions.

    Jadual 1 menunjukkan nombor proton bagi P,Q,R, S dan T. Berdasarkan jadual jawab

    soalan berikut.

    Element Proton Number

    P 3

    Q 8

    R 9

    S 18

    T 19

    TABLE 1

    (a) (i) Write the electron arrangement for the element T .Tuliskan susunan elektron bagi unsur T.

    2.8.8.1

    [1 mark]

    (ii) Determine the position of T in the Periodic Table of elementsTentukan kedudukan unsur T dalam jadual berkala.

    Group 1 and period 4

    [1 mark]

    (b) Name the elements that are placed in the same group in the Periodic table of

    elements.Namakan semua unsur yang berada dalam kumpulan yang sama dalam jadual

    berkala.

    Element P and Element T

    [1 mark]

    (c) Which element is known as a noble gas ?

    Unsur yang manakah dikenali sebagai gas adi ?

    Element S

    [1 mark]

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    KEMENTERIAN PELAJARAN MALAYSIA

    2

    Figure 1 below shows a portion of the Periodic table with elements Q,R,T ,X Y and Z .

    The letters do not represent the symbol of the elements.Rajah 1 menunjukkan jadual berkala dengan unsur-unsur Q,R,T,X,Y dan Z.

    Huruf-huruf tidak menunjukkan simbol yang sebenar bagi unsur.

    FIGURE 1

    (a) Using the alphabets in the table answer the following questions.

    Dengan menggunakan huruf-huruf didalam jadual jawab soalan berikut.

    (i) Which element is a halogenUnsur yang manakah adalah halogen.

    Element Y

    [1 mark]

    (ii) Which element exist as a mono atomUnsur manakah adalah mono atom

    Element R

    [1 mark]

    (b) Write the electron arrangement for Q

    Tuliskan susunan electron bagi Q2.4

    [1 mark]

    (c) Write the formula of the ion formed from Y.

    Tuliskan formula ion yang terbentuk dari atom Y.

    Y-1

    [1 mark]

    (d) What is the name of the group of elements where Z is placed?

    Apakah nama kumpulan dimana unsur Z diletakkan.

    Transition element

    [1 mark]

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Group

    Period

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    BAHAGIAN KURIKULUM TEKNIK DAN VOKASIONAL

    KEMENTERIAN PELAJARAN MALAYSIA

    (e)

    Based on the above information, which gas is more suitable to be used in

    meteorological balloons?Berdasarkan maklumat yang diberi, gas yang manakah lebih sesuai digunakan

    didalam belon kaji cuaca.

    Helium gas

    [1 mark]

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Helium gas

    Gas Helium

    Light

    ringan

    not reactive

    tidak reaktif

    colourless

    tidak berwarna

    Hydrogen gas

    Gas hidrogen

    Lightringan

    Flammable

    Mudah terbakar

    Colourless

    Tidak berwarna

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    PAPER 3

    1. Diagram below shows the chemical symbols which represent three elements X,Y and Z. X,Y and Z is not the actual symbol of the elements.

    Rajah dibawah menunjukkan simbol kimia yang mewakili unsur X,Y dan Z. X,Y dan Z

    bukan simbol sebenar bagi unsur.

    (a) Write the electron arrangement of atoms X, Y and Z.Tuliskan susunan elektron bagi atom X, Y dan Z [ 3 marks]

    X - 2.4

    Y 2.6

    Z 2.8.8.1

    (b) Explain what is meant by the numbers 12 and 6 in the chemical symbol of element X.

    Apakah yang ditunjukkan dengan nombor 12 dan 6 pada simbol kimia bagi unsur X[ 2 marks ]

    in atom X , 12 is stand for nucleon number while 6 is a proton number.

    (c) State the number of neutrons in an atom of atom Y.

    Tentukan bilangan neutron bagi atom Y [1 mark]

    Neutron - 8(d) (i) State the group of atom Z

    Tentukan kumpulan bagi atom Z [1 mark]

    Group 1

    (ii) State the period of atom Z

    Tentukan kala bagi atom Z [1 mark]

    Period 4

    (iii) Explain the reason for the answers in (d)(i) and (d)(ii).

    Berikan alasan bagi jawapan anda di (d)(i) dan (d)(ii). [2 mark]

    Group 1 because electron valens is 1

    Period 4- because has 4 shells filled with electrons

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    12

    X6

    16

    Y8

    39

    Z19

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    OBJECTIVE QUESTION

    1 B 6 C

    2 C 7 C

    3 D 8 C

    4 C 9 A

    5 A 10 B

    PAPER 2

    1. Table 1 shows the proton number and nucleon number for atoms U, Vand W.

    Jadual 1 menunjukkan nombor proton dan nombor nukleon bagi atom U, V dan W.

    Atom Proton number Nucleon number

    U 16 32

    V 17 35

    W 17 37

    Table 1

    a) What is meant byproton number?Apakah yang dimaksudkan dengan nombor proton?

    The number of protons in the nucleus of an atom.

    [1 mark]b) What is the number of neutron in atom ofV?

    Berapakah bilangan neutron dalam atom V?

    18.

    [1 mark]

    c) Which atoms are isotopes? Explain your answer.Atom-atom yang manakah adalah isotop? Terangkan jawapan anda.

    V and W. Both the atoms have the same number of protons but different

    number of neutrons.[2 marks]

    d) i. Write the electron arrangement for atom U.Tuliskan susunan elektron bagi atom U.

    2.8.6

    [1 mark]

    ii. Draw the electron arrangement for atom U.

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    MODULE 2MODULE 2

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    Lukiskan susunan elektron bagi atom U.

    [2 marks]

    2. Diagram 1 shows the chemical symbols which represent three elements X, Y and Z.

    Rajah 1 menunjukkan simbol yang mewakili tiga unsur X, Y dan Z.

    Diagram 1

    b) Element X and Y react to form an ionic compound while element Z and Y react

    to form a covalent compound. Describe the formation of the chemicalcompounds between

    Unsur X dan Y bertindak balas untuk membentuk sebatian ionik, manakala

    unsur Z dan Y bertindak balas untuk membentuk sebatian kovalen . Huraikanpembentukan sebatian kimia antara

    i. element X and Yii. element Z and Y

    Guided answer;

    i. Formation of ionic compound between element X and Y.

    Atom X has an electron arrangement of 2.8.1

    Atom Y has the electron arrangement of 2.8.7

    One atom of X donates one electron to form ion X+ to achieve a stable (octet)electron arrangement.

    One atom of Y receives one electron to form ion Y- to achieve a stable (octet)

    electron arrangement.

    Ion X+ and ion Y- are attracted together by the strong electrostatic forces to

    form an ionic compound with the formula XY.

    ii. Formation of covalent compound between element Z and Y.

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    X23

    11 Y35

    17 Z12

    6

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    Electron arrangement of atom Z is 2.4

    Electron arrangement of atom Y is 2.8.7

    Atom Z needs 4 electrons, while atom Y needs 1 electron to

    achieve the stable electron arrangement.

    Thus, one atom of Z shares 4 pairs of electron with 4 atoms of Y

    forming a molecule of covalent compound with the formula ZY4

    PAPER 3

    3. Diagram 2 shows the set-up of apparatus for an experiment to compare thereactivity of alkali metal towards their reaction with oxygen.

    Rajah 1 menunjukkan susunan radas bagi satu eksperimen untuk membandingkan

    kereaktifan logam alkali terhadap oksigen.

    Diagram 2

    The experiment is carried out using a small piece of lithium, potassium and sodium

    respectively to react with oxygen gas.

    Observation on the alkali metals in the experiment are given in Table 2.Eksperimen dijalankan dengan menggunakan kepingan kecil litium, kalium and

    natrium untuk bertindak balas dengan gas oksigen.

    Pemerhatian ke atas logam-logam alkali dalam eksperimen ditunjukkan dalam

    Jadual 2.

    Set Type of alkali metals

    Jenis logam alkali

    Observations

    Pemerhatian

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Gas jar

    Oxygen gas

    Alkali metal

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    I Lithium Lithium burns slowly and produces white

    fume.

    Litium terbakar dengan perlahan danmenghasilkan wasap putih.

    II Sodium Sodium burns rapidly and produce white

    fume.

    Natrium terbakar dengan cepat dan

    menghasilkan wasap putih.

    III Potassium Potassium burns very rapidly and produce

    white fume.

    Kalium terbakar dengan sangat cepat danmenghasilkan wasap putih.

    Table 2

    a) State one hypothesis for the experiment.

    Nyatakan satu hipotesis bagi eksperimen itu.

    The reactivity of alkali metals increases when going down Group 1.

    [3 marks]b) Based on the experiment, complete the table below.

    Berdasarkan eksperimen tersebut, lengkapkan jadual di bawah.

    Manipulated Variable:

    Pembolehubahdimanipulasikan:

    Type of alkali metals

    Method to manipulate the variable:

    Kaedah memanipulasikan pembolehubah:

    Use different type of alkali metals.

    Responding variable:

    Pembolehubah bergerak balas:

    Reactivity of alkali metals

    What to observe in the responding

    variable:Apakah yang diperhatikan dalam

    pembolehubah bergerak balas:

    Observe the burning of alkali metals

    when react with oxygen.

    Fixed variable:

    Pembolehubah dimalarkan:

    Oxygen gas// size of alkali

    metals

    Method to maintain the fixed variable:

    Kaedah menetapkan pembolehubahdimalarkan:

    Use oxygen gas in each experiment // Use

    the same size of alkali metals

    [6 marks]

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

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    c) Based on the observations in Table 2, arrange lithium, potassium and sodium indescending order of reactivity towards oxygen.

    Berdasarkan pemerhatian dalam Jadual 2, susunkan litium, kalium dan

    natrium mengikut tertib kereaktifan logam terhadap oksigen secara menurun.

    Potassium , sodium , lithium.

    [3 marks]

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

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    OBJECTIVE QUESTION

    1 D

    2 C

    3 D

    4 D

    5 B

    PAPER 2

    1. Figure 1 shows a set of apparatus used to electrolyse molten potassium bromide,KBr using carbon electrodes.

    Gambarajah menunjukkan radas yang digunakan bagi mengelektrolisiskan kalium

    bromida, KBr menggunakan elektrod karbon.

    Figure 1

    a. Draw an arrow to show the direction of electron flow in the diagram.Lukis anak panah untuk menunjukkan arah pergerakan elektron pada rajah

    tersebut. [1 mark]

    b. Write the formula of ions present in the electrolyte.

    Tuliskan formula ion yang hadir dalam elektrolit.

    Pb2+, Br-,

    [1 mark]

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    MODULE 3MODULE 3

    Elektrolit leburan plumbum

    (II) bromida

    Mangkuk pijar

    Panaskan

    ee

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    Elektrod karbon

    BAHAGIAN KURIKULUM TEKNIK DAN VOKASIONAL

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    c. Identify the electrode that act as anode and cathode.Kenalpasti elektrod yang bertindak sebagai anod dan katod.

    i. Electrode X : Anode

    ii. Electrode Y : Cathode[ 2 mark]

    d. Diagram 2 below shows electrolyse cell.

    Rajah 2 di bawah menunjukkan sel elektrolisis

    Diagram 2

    Rajah 2

    i) Write the formula of all the ions present in the copper (II) sulphate solution. Tuliskan formula semua ion yang hadir dalam larutan kuprum (II) sulfat.

    Cu 2+, SO42-, H+, OH -

    [1mark]

    ii) Name the ions attacted to :

    Namakan ion yang tertarik ke:

    a) Anode: hydroxide ion

    b) Cathode: copper ion[2mark]

    iii) State the energy conversion occur in the cell.

    Nyatakan perubahan tenaga yang berlaku dalam sel.

    Electrical energy to chemical energy

    [1mark]

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Copper(II)sulphate

    solution

    Carbon

    electrode

    Larutan kuprum (II) sulfat

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    2.

    a) State the energy conversion occur in voltaic cell .Nyatakan perubahan tenaga yang berlaku dalam sel kimia.

    Chemical Energy to Electrical energy

    [ 1 mark ]

    b) List the ions contain in the electrolyte.

    Senaraikan ion-ion yang terkandung di dalam elektrolit.

    Na+, NO3-, H+, OH-

    [ 1 mark ]

    c) Give one device which can be used to replace the function of voltmeter.

    Berikan satu alat yang boleh digunakan untuk menggantikan fungsi voltmeter.

    Bulb/ Galvanometer

    [ 1 mark ]

    d) State 2 differences of voltaic cell compared to electrolysis cell. Nyatakan 2 perbezaan sel kimia berbanding sel elektrolisis.

    -Energy conversion (chemical energy to electrical energy in voltaic cell and

    vice versa)

    -Cell structure (voltaic cell do not need a dry cell while electrolysis cell need)

    [ 2 mark ]

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Kuprum

    Larutan natrium nitrat

    Logam lain

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    PAPER 3

    Answerall question.

    1. Figure 1 shows an experiment to construct an electrochemical series by measuring thevoltage of a pair of metals in a simple voltaic cell

    Rajah 1 menunjukkan satu eksperimen untuk membentuk satu siri elektrokimia

    dengan cara mengukur nilai voltan pasangan logam dalam satu sel kimia.

    Figure 1/Rajah 1

    Figure 2/Rajah 2

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Logam lain

    Larutan natrium nitrat

    Kuprum

    ee

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    Figure 2 shows the reading on the volmeter in different sets of experiment

    Rajah 2 menunjukan bacaan voltmeter dalam set eksperimen yang berbeza

    (a) Write the voltage for each experiment in the spaces provided in the table below

    Tuliskan nilai voltan untuk setiap eksperimen di dalam jadual yang diberikan

    ExperimentEksperimen Positive terminalTerminal positif Negative terminalTerminal negatif Voltage/VVoltan/V

    1 Copper

    Kuprum

    Magnesium

    Magnesium2.5

    2 Copper

    Kuprum

    Iron

    Ferum0.8

    3 Copper

    Kuprum

    Lead

    Plumbum0.4

    4 Copper

    Kuprum

    Zinc

    Zinc1.1

    (b) Show the direction of electron flow on figure 1.

    Tunjukkan arah pergerakan elektron pada gambarajah 1.

    [3 marks]

    (c) What is the function of voltmeter in voltaic cell.

    Apakah fungsi voltmeter di dalam sel kimia.

    To measure the reading of voltage[3 marks]

    (d) Arrange the metals in (a) in the electrochemical series in ascending order.

    Susun logam dalam soalan (a) dalam siri elektrokimia mengikut tertib menaik.

    Mg, Zn, Fe, Pb, Cu[3 marks]

    (d) Explain why copper be a positive terminal compare to its metal pair base on the

    arrangement of metal in electrochemical series.

    Jelaskan mengapa kuprum bertindak sebagai terminat positif berbanding pasangan

    logamnya berpandukan kepada aspek susunan logam di dalam siri elektrokimia.

    Because is place lowest compared to other metals in electrochemical series/

    Copper is less electropositive metal[3 marks]

    (e) Another voltaic cell is formed by using magnesium and iron as electrodes. Which

    electrode will be the positive terminal?

    Satu sel kimia yang lain dibina dengan menggunakan magnesium dan ferum sebagai

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

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    elektrod.Elektrod yang manakah akan bertindak sebagai terminal positif?

    Iron[3 marks]

    PAPER 2

    PAPER 3

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Objective Question

    1 B2 A

    3 C4 A5 B

    Question Answer

    1 (a) 2NH3 (g) + 3H2 (g)

    2NH3 (g)

    (b)(i)

    Ammonium nitrate

    Ammonium sulphate

    (b) (ii)NH4NO3NH4SO4

    MODULE 4MODULE 4

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    Question Answer

    1 (a)

    Experiment I : 1.1 V

    Experiment II : 2.7 VExperiment III : 2.0 V

    Experiment IV : 0.8 V

    Experiment V : 0.5 V( score 3: all corrects value includes units )

    (b)

    Experiment Negative terminal Voltmeter reading (V)

    Experiment I P 1.1

    Experiment II Q 2.7

    Experiment III R 2.0

    Experiment IV S 0.8

    Experiment V T 0.5

    (c)

    (i) metal at negative terminal / two different metals / pairs of two

    different metals.. (any one )

    (ii) voltmeter readings / potential differences ( any one )

    ( iii ) copper metal / volume and concentration of copper(II) sulphatesolution./ voltmeter ( any one )

    ( total score : 3 )

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    PAPER 3

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Question Answer

    (d)

    The further the distance between two metals in Electrochemical series,the voltage/ potential difference is higher/larger

    or

    (e )

    (i) The voltage / potential difference in Experiment II is larger than in

    Experiment I

    or

    The voltage / potential difference in Experiment I is lower / smallerthan in Experiment II.

    Any one : 3 marks

    (ii) Metal Q is more electropositive than metal P

    The distance of metal P is nearer to copper compared to metal Q

    in Electrochemical series.

    The arrangement is Q, P and copper in the Electrochemicalseries in descending order.

    3 marks

    (f) Q , R, P , S , T , Cu3 marks

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    AnswerProblem Statement Are alloy is harder than pure metals

    All variables

    - Manipulated Variable : Different types of materials

    ( aluminium and duralumin )

    -Responding Variable : Diameter of dent

    - Constant Variable : Diameter of steel ball bearing,Height of the weight,

    mass of the weight.

    Hypothesis

    Alloy is harder than pure metal /

    Duralumin is harder than aluminium

    List of materials

    and apparatus

    Materials : aluminium block, duralumin block and

    cellophane tape.

    Apparatus : retort stand and clamp, one kilogram weight, steel ball

    bearing, metre rule and thread.

    Procedure

    1. A cellophane tape is used to to stick a steel ball bearing onto the

    aluminium block.

    2. A weight is hung above the ball bearing at a height of 50 cm.3. The weight is dropped so that it hits the ball bearing.

    4. The diameter of the dent made on the aluminium block is

    measured.

    5. Steps 1 to 4 is repeated twice.6. By replacing aluminium block with the duralumin block, steps 1 to

    5 is repeated.

    7. The readings are recorded in the table below.

    Tabulation of data

    Type of block /

    material

    Diameter of dents

    ( cm )

    Average diameter

    (cm )

    1 2 3Duralumin

    Aluminium

    MODUL 5MODUL 5

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    Question Answer

    1 (a) 2HCl + CaCO3 CaCl2 + CO2 + H2O

    (b) Rate of reaction = 32 / 50 = 0.64 g/cm3

    (c) (i)

    (c)(ii)

    1- Draw a triangle on the graph - 1 mark

    2- Rate of reaction = 18 / 77.5 - 1 mark

    = 0.23 cm3 / s

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    3.

    (a)

    1. antibiotic2. This is to make sure that all the bacteria are killed.

    3. Otherwise, patient B may become ill again

    4. bacteria may become more resistant to the antibiotic.5. As a result, the antibiotic is no longer effective.

    1 MALAYSIA : RAKYAT DIDAHULUKAN, PENCAPAIAN DIUTAMAKAN

    Question Answer

    2 (a)Heat of displacement is the heat change when one mole of a metal isdisplaced from its salt solution by a more electropositive metal.

    (b)

    The intensity of blue solution ( copper(ll) sulphate solution ) in this

    reaction decreases until they become colourless.

    (c) Zn + Cu 2+ Zn 2+ + Cu

    (d)

    (i) Number of mole of copper(ll) ions= MV1000

    = 2(25)

    1000= 0.005 mole.

    (ii) mc = 25 x 4.2 x 9.5 = 997.5 joule

    (iii) The heat of displacement of copper by zinc

    997.5

    = ----------0.005

    = 199500 J

    = 199.5 kJ/mol

    (e)

    Energy

    Zn + Cu 2+

    H = -199. 5 kJ/mol

    Zn 2+ + Cu

  • 7/31/2019 Chemist Marking Scheme (Main)1

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    BAHAGIAN KURIKULUM TEKNIK DAN VOKASIONAL

    KEMENTERIAN PELAJARAN MALAYSIA

    (b)

    A: Hydrophobic part

    B: Hydrophilic partPart A is dissolved in oil / grease

    Part B is dissolved in water

    (c) (i)

    Procedure:1. Two basins/beakers are filled with hard water.2. Soap is added to one beaker and detergent is added to another beaker.

    3. A piece of dirty cloth is placed into each beaker and agitated.

    4. Observations:

    Soap in hard water Detergent in hard water

    1. cloth not clean

    2. scum forms

    3 water less dirty

    1. cloth clean

    2. no scum

    3. water turns dirty

    (any one pair)

    5. Conclusion: detergent cleans stains more effectively than soap.

    (c) (ii):

    1. soap particles dissolve in water and (reduce the surface tension of water)/(water wet the cloth thoroughly)

    2. the hydrophilic part dissolve in water while the hydrophobic part dissolves in

    grease//diagram3. During cleaning/rubbing/heating/scrubbing, grease is lifted off the surface

    4. Hydrophobic part / soap anion surrounded the grease//diagram

    5. Grease is broken up into small droplets/forming an emulsion//diagram

    6. When rinsed, the grease droplet will be removed