Chem juj k1+k2+k3 (skema jawapan) [set 1]

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  • SKEMA PRAKTIS BESTARI JUJ KIMIA SET 1 KERTAS 1, 2 & 3

    4541 Set 1 Hak Cipta JUJ Pahang 2017 1

    SKEMA JAWAPAN KERTAS 1

    JUJ KIMIA SET 1 2017

    1 A 11 D 21 C 31 D 41 A

    2 D 12 A 22 B 32 B 42 A

    3 B 13 C 23 B 33 B 43 D

    4 B 14 A 24 B 34 C 44 D

    5 C 15 A 25 C 35 B 45 A

    6 D 16 C 26 A 36 B 46 D

    7 A 17 C 27 B 37 A 47 B

    8 D 18 A 28 B 38 B 48 B

    9 C 19 C 29 D 39 A 49 C

    10 A 20 C 30 B 40 B 50 B

  • SKEMA PRAKTIS BESTARI JUJ KIMIA SET 1 KERTAS 1, 2 & 3

    4541 Set 1 Hak Cipta JUJ Pahang 2017 2

    MARKING SCHEME PAPER 2 SET 1 JUJ CHEMISTRY 2017

    Question No. Mark Scheme Sub

    Mark Mark

    1 (a) Horizontal rows of elements in the Periodic Table of

    elements

    1 1

    (b) Atoms have three shells filled with electron 1 1

    (c) 2.8.5 1 1

    (d) (i) 1. Atom has achieved stable octet electron arrangement

    // atom has eight valence electron

    2. Atom does not receive, donate or share electron with

    other atom

    1

    1

    2

    (ii) Aluminium / Al 1 1

    (iii) Al2O3 1 1

    (e)

    pH value pH 2 pH 13

    Oxide of element SO2 Na2O

    1 + 1

    2

    TOTAL 9

    Question No. Mark Scheme Sub

    Mark Mark

    2 (a) (i) Oil // Fats 1 1

    (ii) Ester 1 1

    (iii) Saponification 1 1

    (b) (i) A: Soap

    B: Detergent

    1

    1

    2

    (ii) Magnesium ion/ Mg2+

    // Calcium ion/ Ca2+

    1 1

    (c) (i) Ethene 1 1

    (ii)

    1 1

    (iii) - It is non biodegradable//

    - Produce poisonous/toxic gas when burn//

    - Improper disposal, clog the drain//

    - Improper disposal, place for mosquito breeding.

    [Any one]

    1 1

    TOTAL 9

  • SKEMA PRAKTIS BESTARI JUJ KIMIA SET 1 KERTAS 1, 2 & 3

    4541 Set 1 Hak Cipta JUJ Pahang 2017 3

    Question No. Mark Scheme Sub

    Mark Mark

    3 (a) (i) NO2 1 1

    (ii) 1. Correct number of atoms and nucleus is shown.

    2. Correct number of electron in each shell and correct

    number of electron shared.

    1

    1

    2

    (iii) molecule 1 1

    (iv) 1. Correct formula of reactants and products

    2. Balanced equation

    N2 + 2O2 2NO2

    1

    1

    2

    (b) (i) Ionic bond 1 1

    (ii) 1. Magnesium atom donates two electrons to

    form Mg2+

    2. Oxygen atom receive two electrons to form O2-

    1

    1

    2

    (iii) High melting/ boiling point //

    Can conduct electricity in molten/ aqueous solution//

    Soluble in water//Insoluble in organic solvent

    1

    1

    TOTAL 10

    Question No. Mark Scheme Sub

    Mark Mark

    4 (a) Heat change when one mol of metal is displace from its

    salt solution by a more electropositive metal.

    1 1

    (b) To reduce heat loss to the surrounding. 1 1

    (c)

    Temperature increase // Brown solid deposited// Blue

    colour of CuSO4 become paler

    1 1

    (d)

    (i) H = 100(4.2)(10) J // 4200 J // 4.2 kJ 1 1

    (ii) 1. number of mole

    2. Heat of displacement with correct unit and negative

    sign

    1

    1+1

    3

  • SKEMA PRAKTIS BESTARI JUJ KIMIA SET 1 KERTAS 1, 2 & 3

    4541 Set 1 Hak Cipta JUJ Pahang 2017 4

    Question No. Mark Scheme Sub

    Mark Mark

    n = // 0.05

    H = - J mol-1 // 84000 Jmol-1 // 84 kJmol-1

    (e) Exothermic reaction 1 1

    (f)

    1. Magnesium // [Any metal higher place than copper in

    the electrochemical series]

    2. Located higher than copper in the electrochemical

    series // More electropositive than copper

    1

    1

    2

    TOTAL 10

    Question No. Mark Scheme Sub

    Mark Mark

    5 (a) (i) Double decomposition reaction 1 1

    (ii) Lead(II) nitrate / Pb(NO3)2

    Sodium carbonate / Na2CO3 // Potassium carbonate/

    K2CO3// Ammonium carbonate/ (NH4)2CO3

    1

    1

    2

    (iii) 1. Correct formula of reactants and products

    2. Balanced equation

    Pb(NO3)2 + Na2CO3 Pb CO3 + 2NaNO3

    1

    1

    2

    (iv) White 1 1

    (b)

    (i) Sodium carbonate / Na2CO3 // Potassium carbonate /

    K2CO3 // Ammonium carbonate / (NH4)2CO3

    1

    1

    (ii) Cu2+

    + CO32-

    CuCO3 1 1

    (iii) 1. Pour the treated waste water into a test tube.

    2. Add sodium hyroxide solution into the test tube.

    3. Blue precipitate does not formed.

    OR

    1. Pour the treated waste water into a test tube.

    2. Add ammonia aqueous into the test tube.

    3. No change.

    1

    1

    1

    3

    TOTAL 11

  • SKEMA PRAKTIS BESTARI JUJ KIMIA SET 1 KERTAS 1, 2 & 3

    4541 Set 1 Hak Cipta JUJ Pahang 2017 5

    Question No. Mark Scheme Sub

    Mark Mark

    6 (a) (i) K+, Cl

    -, H

    +, OH

    - 1 1

    (ii) Bubble gas released // colourless gas released 1 1

    (iii) R: Chlorine

    T: Oxygen

    1

    1

    2

    (b) (i) Copper(II) sulphate / CuSO4 // Silver nitrate /AgNO3 //

    Sodium chloride / NaCl //

    [Any suitable electrolyte]

    1

    1

    (ii) V, W, Z, Y, X 1 1

    (iii) 1. V and X

    2. 2.80 V

    1

    1

    2

    (iv) 1. Silver

    2. Silver is located below copper in

    electrochemical series// Silver is less

    electropositive than copper

    1

    1

    2

    (c) Electrical energy to chemical energy 1 1

    TOTAL 11

    Question No. Mark Scheme Sub

    Mark Mark

    7 (a) (i) 1. Solvent L : Propanon // methylbenzene // [any

    suitable organic solvent]

    2. Solvent M : Water

    Beaker A Beaker B

    3 No gas bubbles release

    // No change

    Gas bubbles release //

    colourless gas X

    collected in the syringe

    4 HCl does not ionise // no

    H+ ion // HCl exist as

    molecule

    HCl ionise // present of

    H+ ion

    5 No reaction Reaction occur

    6 Blue litmus paper does

    not change colour

    Blue colour litmus paper

    change to red

    1

    1

    1

    1

    1

    1

    6

    (ii) 3. Correct formula of reactants and products

    4. Balanced equation

    5. Number of mole

    6. Mole ratio

    7. Molar mass of CaCO3

    8. Mass with correct unit

    1

    1

    1

    1

    1

    1

    6

  • SKEMA PRAKTIS BESTARI JUJ KIMIA SET 1 KERTAS 1, 2 & 3

    4541 Set 1 Hak Cipta JUJ Pahang 2017 6

    Question No. Mark Scheme Sub

    Mark Mark

    CaCO3 + 2HCl CaCl2 + H2O + CO2

    Moles gas = // 0.001

    1 moles gas X produced from 1 moles CaCO3 //

    0.001 moles gas X produced from 0.001 moles CaCO3

    Molar mass CaCO3 = 40 + 12 + 3(16) // 100

    Mass CaCO3 = 0.001 x 100 g // 0.1g

    (b) (i) 1. HX : HCl // HNO3

    2. H2Y: H2SO4

    3. HZ : CH3COOH

    Compare pH value of acid H2Y and acid HX.

    H2Y is diprotic acid //

    1 mole of H2Y ionise in

    water produce 2 moles

    of H+ ion

    HX is monoprotic acid //

    1 mole of HX ionise in

    water produce 1 moles

    of H+ ion

    4. Concentration of H+ ion in H2Y is higher than in HX

    5. The higher the concentration of H+ ion the lower the

    pH value

    1

    1

    1

    1

    1

    1

    (ii) Compare pH value of acid HZ and acid HX.

    HZ is a weak acid // HZ

    ionise partially in water

    produce lower

    concentration of H+ ion

    HX is a strong acid // HX

    ionise completely in

    water produce higher

    concentration of H+ ion

    The lower the concentration of H+ ion the higher the

    pH value

    1

    1

    8

    TOTAL 20

  • SKEMA PRAKTIS BESTARI JUJ KIMIA SET 1 KERTAS 1, 2 & 3

    4541 Set 1 Hak Cipta JUJ Pahang 2017 7

    Question No. Mark Scheme Sub

    Mark Mark

    8 (a) 1. Fe: +3

    2. Mg: +2

    3. Fe2O3: Iron(III) oxide

    4. MgO : Magnesium oxide

    5. Iron has roman numeral because it has more

    than one oxidation number

    6.Magnesium has no roman numeral because it

    has only one oxidation number

    1

    1

    1

    1

    1

    1

    6

    (b) 1. Glucose undergoes oxidation

    2. by losing hydrogen

    3. Oxygen undergoes reduction

    4. by gaining hydrogen

    1

    1

    1

    1

    4

    (c) 1. Reaction I : +3 +2

    2. Reaction II: +2 0

    3. Reaction III: +2 +3

    4. Metal X: Magnesium//Zinc//Aluminium

    5. Substance Y: Magnesium//Zinc//Aluminium

    6. Substance Z: Bromine

    7. Reaction II:

    1. Correct formula of reactants and products

    2. Balanced equation

    Fe2+

    + Zn Fe + Zn2+

    8. Reaction III:

    1. Correct formula of reactants and products

    2. Balanced equation

    2 Fe2+

    + Br2 2 Fe3+

    + 2Br-

    1

    1

    1

    1

    1

    1

    1

    1

    1

    1

    10

    TOTAL 20

    Question No. Mark Scheme Sub

    Mark Mark

    9 (a) 1. Temperature

    2. Time taken for clothes to dry in situation II is shorter

    compare to situation I // Clothes in situation II dry

    faster than in situation I.

    3. Temperature in situation II is higher than situation I

    4. Kinetic energy