Chem JUJ K1 K2 K3 Skema Jawapan SET 1

(1)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} 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

(2)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₂ MARKING SCHEME PAPER 2 SET 1 JUJ CHEMISTRY 2017

Question No. Mark Scheme Sub

Mark ΣMark 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

- Produce poisonous/toxic gas when burn// - Improper disposal, clog the drain//

- Improper disposal, place for mosquito breeding. [Any one]

1 1

(3)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₃ 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 O

2-1

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

Mark ΣMark 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

(4)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₄

2. Located higher than copper in the electrochemical series // More electropositive than copper

Sodium carbonate / Na2CO3 // Potassium carbonate/ K2CO3// Ammonium carbonate/ (NH4)2CO3

1

1 2

(iii) 1. Correct formula of reactants and products 2. Balanced equation

(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 3

(5)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₅ Mark

6 (a) (i) K+, Cl-, H+, OH- 1 1

(ii) Bubble gas released // colourless gas released 1 1 (iii) R: Chlorine electrochemical series// Silver is less electropositive than copper

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

(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

(6)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₆ 0.001 moles gas X produced from 0.001 moles CaCO3

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

water produce 2 moles of H+_ion

HX is monoprotic acid // 1 mole of HX ionise in water produce 1 moles of H+_ion ionise partially in water produce lower

The lower the concentration of H+_{ion the higher the}

pH value

1

1 8

(7)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₇ 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

(b) 1. Glucose undergoes oxidation 2. by losing hydrogen

3. Oxygen undergoes reduction 4. by gaining hydrogen

1

4. Metal X: Magnesium//Zinc//Aluminium 5. Substance Y: Magnesium//Zinc//Aluminium 6. Substance Z: Bromine

7. Reaction II:

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 of particles in situation II is higher

than situation I

5. The rate of water particles evaporate in situation II is higher than situation I

(8)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₈

Mark ΣMark (b) (i) 1. Correct formula of reactants and products

2. Balanced equation

3. Rate of reaction set II with correct unit. 4. Rate of reaction set III with correct unit.

Mg + 2HNO3  Mg(NO3)2 + H2

(ii) Time taken for magnesium dissolved in set II is shorter than set I

1. Concentration of nitric acid in set II is higher than set I

2. Number of particles / H+_{ion perunit volume is}

higher

3. Frequency of collision between Mg and H+_{ion is}

higher

4. Frequency of effective collision is higher 5. Rate of reaction in set II is higher.

Time taken for Magnesium dissolved in set III is shorter than set II

6. Temperature in set III is higher than set II 7. The kinetic energy of particles is higher

8. Frequency of collision between Mg and H+_{ion is}

higher

9. Frequency of effective collision is higher 10.Rate of reaction in set III is higher.

(9)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₉ Mark

10 (a) 1. Process I : Dehydration 2. Process II : Esterification

3. Homologous series compound P : Alcohol 4. Compound P : Hydroxyl group / -OH

5. Compound Q : Double covalent bond between carbon atoms / C=C

6. Compound R : Carboxyl group / -COOH

1

(b) 1. Correct formula of reactants and products 2. Balanced equation

3. Mole ratio

4. Mass with correct unit

C2H5OH  C2H4 + H2O 2. Compound R : Butanoic acid

3. Measure 2 cm3_{of glacial ethanoic acid and pour into}

a boiling tube

4. Add 2 cm3_{of absolute ethanol into the boiling tube}

5. Add few drops of concentrated sulphuric acid and shake

6. Heat the mixture

7. Pour the mixture into a beaker of water 8. Pineapple smell // sweet fruity smell

9. C2H5OH + C3H7COOH  C3H7COO C2H5 + H2O

(10)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₁₀ PERATURAN PEMARKAHAN KIMIA KERTAS 3 JUJ 2017 SET 1

Soalan Pemarkahan Markah

1(a)

Able to record all reading accurately to one decimal point and with

unit.

Sample answer:

Initial temperature : 60.0 oC

Temperature at 1 min : 67.0 oC

3

Able to record all readings correctly without decimal point//

Able to record 5-6 readings correctly 2

Able to record 3-4 readings correctly 1

No response or wrong response 0

1(b)

Able to plot a graph that contains the following information.

- Axes labeled with units

- All the 8 points transferred correctly

- A smooth curve is drawn

- Uniform scale Sample answer:

Temperature/oC

Time/min

(11)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₁₁

1(c)

Able to state the melting point with 1 decimal place and show on the graph correctly

Sample answer:

Temperature/oC

80.0

Time/min

3

Able to give an idea to plot a graph

Sample answer:

1

(12)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₁₂

1(c)

Able to state the melting point correctly without decimal place but with correct unit without showing on the graph//Able to state the melting point on the curve

Sample answer:

Melting point of naphthalene: 80 oC //

Temperature, oC

Melting point

Time/min

2

1(c)

Able to state the melting point less accurately without unit and without decimal place // Able to show the melting point incorrectly;

Sample answer:

Melting point of naphthalene : 80 //

Temperature/oC

Melting point

Time/min

1

(13)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₁₃ 1(d)

Able to explain correctly according to 3 information :

- Heat energy absorbed

- is used to over come the forces of attraction between the molecules

Sample answer:

Heat energy absorbed is used to overcome the forces of attraction

between the molecules 3

Able to explain less accurately

Sample answer:

The heat energy is used to overcome the forces of attraction

2

Able to state an idea

Sample answer:

The heat energy is used/absorbed//solid turn to liquid//the heat energy is used to overcome the forces.

1

(14)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₁₄

1(e)

Able to predict the temperature at the 8th minutes with unit and decimal place correctly

Answer:

101.0 0C

3

Able to predict the temperature at the 8th minutes without unit and decimal place correctly

Sample answer:

101.0 // 101 0C //101

2

Able to predict the temperature at the 8th minutes less correctly

Sample answer:

Lebih dari 94. 0C // [102 ≤ X ≤ 105] // [95 ≤ X ≤ 100]

1

(15)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₁₅ 1(f)

Able to classify all the compound correctly

Sample answer:

Ionic compound Covalent compound

Potassium bromide

Copper(II) sulphate

Aluminium oxide

Ammonia

Methanol

tetrachloromethane

3

Able to classify any 5 compounds correctly. 2

Able to classify at least 2 compound correctly 1

2 (a)

Able to state all observations and inferences correctly. Sample answer:

Experiment Observation Inference

I Bulb does not lights up Cannot conduct electricity// Covalent compound

II Bulb does not lights up Cannot conduct electricity//

Covalent compound

III Bulb lights up Can conduct electricity//

Ionic compound

6

Able to state at least 5 observations and inference correctly 5

Able to state at least 4 observation and inference correctly 4

(16)

4541 Set 1 © _{Hak Cipta JUJ Pahang 2017} ₁₆

2 (b)

Able to state all the variables in this experiment correctly.

Sample answer:

(i) Manipulated variables : Type/different substance/ionic compound

and covalent compound

(ii) Responding variable : electrical conductivity//bulb lights up and

the bulb does not light up

(iii) Constant variable : mass of substance/compound//carbon

electrode

3

Able to state any two variables correctly 2

Able to state any one variable correctly 1

2 (c)

Able to state the relationship between the manipulated variable and the responding variable correctly

Sample answer:

Covalent compound cannot conduct electricity/lights up the bulb and

ionic compound can conduct electricity/lights up the bulb 3

Able to state the relationship between the manipulated variable and the responding variable less correctly

Sample answer:

Covalent compound cannot conduct electricity/lights up the bulb // ionic compound can conduct electricity/lights up the bulb

2

Able to give an idea of hypothesis

Sample answer:

Conduct electricity/bulb lights up

1

(17)

Able to give one operational definition of the experiment correctly with the following aspects:

i) what you do-dip /immerse (carbon electrode )in electrolyte/PbBr2

ii) what you observe-bulb lights up

Sample answer:

1. when carbon electrode is dipped in electrolyte/lead(II) bomide /PbBr2

2. Bulb lights up

3

Able to give the operational definition for electrical conductivity for ionic compound incompletely with any one of the following aspects:

i).what you do

ii).what you observe

Sample answer:

Bulbs lights up/dip carbon electrode in lead(II) bromide/electrolyte

2

Able to give an idea of operational definition for electrical conductivity for ionic compound

Sample answer:

Carbon electrode is dipped / [electrolyte] is used /molten state

1

(18)

3 (a)

Able to state the problem statement with the named of strong acid and weak acid correctly

Sample answer:

Does the heat of neutralisation between hydrochloric acid/(any strong acid) and sodium hydroxide solution is higher than the heat of

neutralisation between ethanoic acid(any suitable weak acid) and sodium hydroxide solution?

3

Able to state the problem statement less correctly

Sample answer:

Does the heat of neutralization between strong acid and weak acid with

strong alkali different ? //To study the heat of neutralization between strong and weak acid with strong alkali.

2

Able to state an idea about problem statement

Sample answer:

Heat of neutralisation is affected by the strength of acid.

1

3 (b)

Able to state the relationship between the manipulated variable and the responding variable and state the direction correctly.

Sample answer:

The reaction between hydrochloric acid/strong acid and sodium hydroxide will give the higher value of heat of neutralization than the

reaction between ethanoic acid/weak acid with sodium hydroxide. 3

Able to state the relationship between the manipulated variable and the responding variable without stating the direction/ less accurately

Sample answer:

Different strength of acid react with sodium hydroxide, different value of heat of neutralisation

2

Able to give an idea of hypothesis

Sample answer:

The strength of acid affect the heat of neutralisation

1

(19)

3(d)

Able to list down the materials and apparatus correctly

Sample answer:

Materials : [0.5-2.0mol dm-3] sodium hydroxide solution,

[0.5-2.0mol dm-3 ] hydrochloric acid, [0.5-2.0 mol dm-3]

ethanoic acid (any suitable strong and weak named acid),

Apparatus : Polystyrene/plastic cup, thermometer, [50-100cm3]

measuring cylinder

3

Able to give the list of the apparatus and materials correctly but not complete

Sample answer:

Sodium hydroxide solution, hydrochloric acid / ethanoic acid, Polystyrene/plastic cup, thermometer,

2

Able to give an idea on the list of the apparatus and substances correctly

Any one materials and any one apparatus

1

No response or wrong response 0 3(c)

Able to state all the variables accurately

Sample answer:

Manipulated variable : Hydrochloric Acid and Ethanoic Acid

(any suitable named strong and weak acid)

//Strong acid and weak acid //X and Y acid

Responding variable : Heat of neutralisation

Fixed variable : Concentration and volume of NaOH

solution//NaOH solution//polystyrene cup // Concentration and volume of acid solution

3

(20)

3(e)

Able to state all the steps of the experiment accurately

Answer:

1. [25-100 cm3] of sodium hydroxide solution is poured into a polystyrene cup using a measuring cylinder.

2. The initial temperature of sodium hydroxide solution is recorded. 3. [25-100cm3] of hydrochloric acid is measured into another

polystyrene cup.

4. The initial temperature of hydrochloric acid is recorded. 5. Hydrochloric acid is then poured quickly into a cup containing

sodium hydroxide solution.

6. The mixture is stirred using thermometer 7. The highest temperature is recorded.

8. Repeat steps 1 to 6 using ethanoic acid instead of hydrochloric acid.

3

Able to state 5 steps of the experiment

Steps 2, 4, 5, 8 2

Able to state 2 minimum steps correctly

Steps 5, 6/7

1

3(f)

Able to construct the table that contains the following information

1. Columns and rows 2. Headings in the table 3. With unit

Sample answer:

Pair of acid/alkali

Initial temperature/ oC Highest temperature of the mixture/o C

Acid Alkali Average

NaOH/HCl

NaOH/CH3COOH

(21)

Able to construct the table that contains the following information

1. Columns and rows 2. Headings in the table 3. Without unit

//Able to state an idea about the tabulation of data

Tabulation of data has the following elements:

Minimum 2 columns and 2 rows

Sample answer:

Pair of acid/alkali

Initial temperature Highest temperature of the

mixture

Acid Alkali

//

Sample answer:

Pair of acid/alkali Temperature

1