Chemistry Perfect Score 2011

BAHAGIAN PENGURUSAN SEKOLAH BERASRAMA PENUH
DAN SEKOLAH KECEMERLANGAN

MODUL PERFECT SCORE
SEKOLAH BERASRAMA PENUH
TAHUN 2011

CHEMISTRY
PANEL PENYEDIA DAN PEMURNI:

Pn. Wan Noor Afifah Binti Wan Yusoff (Ketua) SBPI GOMBAK
Pn. Aishah Peong Binti Abdullah SBPI TEMERLOH
Pn. Norini Binti Jaafar SEKOLAH SULTAN ALAM SHAH
Pn. Noraini Binti Zakaria SMS SULTAN MOHAMAD JIWA
Pn. Rossita Binti Radzak SMS TUANKU MUNAWIR
En Che Malik Bin Mamat SBPI BATU RAKIT
En Jong Kak Ying SMS KUCHING
En Ooi Yoong Seang SMS MUAR
Pn Sa’adah Binti Mohayuddin SMS SERI PUTERI
Pn Faridah Bt Hamat SMS TUANKU MUNAWWIR

Chemistry Perfect Score Module 2011 1

CHEMISTRY PERFECT SCORE MODULE 2011
CONTENT

 Format of an instrument of chemistry
 Construct requirement
Guidelines &  Guidelines for answering paper 1
1
Anwering Techniques  Guidelines for answering paper 2
 Guidelines for answering paper 3
 The common command words in paper 2

 The structure of Atom
 Chemical Formulae and equations
2 Set 1
 Periodic Table of Elements
 Chemical Bonds

 Electrochemistry
3 Set 2
 Oxidation and Reduction

 Acids and Bases
 Salts
4 Set 3
 Rate of reaction
 Thermochemistry

 Carbon compounds
5 Set 4  Manufactured Substance in Industry
 Chemicals for Consumers

 Paper 3 set 1
6 Set 5  Paper 3 set 2
 Paper 3 set 3


CHEMISTRY
PERFECT SCORE MODULE

GUIDELINES
&
ANSWERING TECHNIQUES

CHEMISTRY SPM


GUIDELINES AND ANSWERING TECHNIQUES FOR SPM CHEMISTRY PAPER

1.0 FORMAT OF AN INSTRUMENT OF CHEMISTRY BEGINNING SPM 2003

No Item Paper 1 Paper 2 Paper 3
(4541/1) (4541/2) (4541/3)
1 Type of instrument Objective test Subjective test Written Practical Test
Type of item Objective it Section A : Subjective Item :
Structured Item Structured Item
Section B : Extended Response Item:
2
Essay restricted response Item (Planning an experiment)
Section C :
Essay extended response Item
Number of question 50 (answers all) Section A : 6 (answer all) Structured Item :
Section B : 2 (choose one) 1/2 items (answer all)
3
Section C : 2 (choose one) Extended Response Item :
1 item
5 Duration of time 1 hour 15 minutes 2 hour 30 minutes 1 hour 30 minutes

2.0 CONSTRUCT REQUIREMENT

Construct Paper 1 Paper 2 Paper 3
Knowledge 20 m ( No 1- 20) 14 -
Understanding 15 m ( No 21 – 35) 21 -
Application 15 m ( No 36 – 50) 29 -
Analysis - 21 -
Synthesizing - 15 -
Science process - - 50
Total mark 50 100 50

3.0 TIPS TO SCORE “ A “ CHEMISTRY

3.1 Master the topics that contains the basic concepts of chemistry :
1. The structure of the atom
2. Chemical Formulae And Equations
3. Periodic Table
4. Chemical Bond

3.2 Familiarize with different types of questions as listed below and complete the previous SPM papers:
1. Objectives questions (MCQ) (Paper 1)
2. Structured questions ( Paper 2 & 3)
3. Essays (Paper 2)
4. Planning an experiment ( Paper 3)
5. Draw and label the diagram
6. Writing chemical equation( balanced equation, ionic equation, half equation)

3.3 Try to get :-
 40 marks above for paper 1
 60 marks above for paper 2
 40 marks above for paper 3 (Total = 180/2 =80 , A+ in SPM)

4.0 GUIDELINE FOR ANSWERING PAPER 1

4.1 Paper 1 questions test students on
1. Knowledge ( Number 1 – 20)
2. Understanding ( Number 21 – 35)
3. Application ( Number 36 – 50 )

4.2 Score in paper 1 Indicates student’s level of understanding in chemistry:
Less than 20 – very weak
20 – 25 - weak
26 – 30 - average
31 – 39 - good
40 – 45 - very good
46 – 50 - excellent.

4.3 Answer all SPM objective questions (2003 – 2010). Objective questions for each year contain all topics. If
your score in paper 1 is 40 and above, you will able to answer questions in paper 2 & 3 easily.


5.0 GUIDELINE FOR ANSWERING PAPER 2 (STRUCTURE AND ESSAY)
5.1 Paper 2 questions test student on
1. Knowledge
2. understanding
3. analyzing
4. synthesizing
5.2 Steps taken are:
1. Underline the command word and marks allocated for each question.
2. Match the command word to the mark allocated for each question. 1 point is awarded 1 mark.
3. Follow the needs of the question (Refer to the command words, page …….)
4. Unnecessary repetition of the statement in the question is not required.
5.3 Three types of questions which involve experiments in paper 2:
I. Type 1
Describe an experiment on…………………Include a labeled diagram in your answer
1. Diagram
2. Procedure
3. Observation/example/data/calculation/equation/sketch of graph/conclusion
II. Type 2
Describe an experiment……………( The diagram will support your answer.)
1. No mark is allocated for a diagram
2. Procedures
3. Observation/example/calculation/equation/sketch of graph/conclusion
III. Type 3
Describe a chemical/confirmatory test for …….
1. Procedure
2. Observation
3. Conclusion

6.0 GUIDELINE FOR ANSWERING PAPER 3
6.1 Structure Question 1/2 test the mastery of 11 Scientific Skills
1. Observing
2. Classifying
3. Inferring
4. Measuring (burette , stopwatch, thermometer, voltmeter)
5. Predicting
6. Communicating( e.g construct table and draw graph)
7. Space-Time Relationship
8. Interpreting Data
9. Defining Operationally
10. Controlling Variables
11. Hypothesizing

Each answer is allocated mark as follows: 3 marks/2 marks/1 mark/0 Score : 11 X 3 = 33
Example of operational definition:
1. what you do
2. what you observe correctly
Example:
1. When acid is added into latex, white solid is formed.
When acid is added into latex, latex coagulated.- wrong
2. When the higher the concentration sodium thiosulphate solution is added into sulphuric acid, time taken for `X~ mark to
disappear from sight is shorter.
3. When iron nail is coiled with copper and immersed into jelly mixed with potassium hexacyanoferrate(III) and phenolphthalein
solution, blue spot/colouration is formed.

Operational definition for What you do What is observed
1. Rusting of iron When an iron nail coiled with a less Blue spots are formed
electropositive metal is immersed in hot
agar-agar added with potassium
hexacyanoferrate (III) solution,
2. Coagulation of latex When acid is added to latex White solid is formed
3. Reactivity of Group 1 When a metal which is lower in Group 1 is Brighter flame is formed
elements put in a basin half filled with water
4. Precipitation of silver When silver nitrate solution is added to White solid is formed
chloride sodium chloride solution
5. Voltaic cell When two different metals are dipped into an The needle of the
electrolyte voltmeter deflects
6. An acid When a blue litmus paper is dipped into a Blue litmus paper turns
substance which is dissolved in water, red


Hypothesis: Relate manipulated variable followed by responding variable with direction.
Example:
1. The higher temperature of the reactant the higher the rate of reaction – 3 marks
The temperature of the reactant affect the rate of reaction – 2 marks
2. Hexene decolourised brown bromine water but hexane does not decolourised brown bromine water.
3. When acid is added into latex, latex coagulates, when ammonia is added into latex, latex cannot coagulates

6.2 Question 3 (essay) Test The Mastery of Planning Experiment .
Planning should include the following aspects:
1. Aim of the experiment/Statement of the problem
2. All the variables
3. Statement of the hypothesis
4. List of substances/material and apparatus – should be separated
5. Procedure of the experiment
6. Tabulation of data Score : (5 X 3) + 2 = 17

The question normally starts with certain situation related to daily life.
Problem statement/ aim of the experiment / hypothesis and variable can be concluded from the situation given.
State all the variables
Manipulated variable :
Responding variable :
Constant variable: list down all the fixed variables to ensure the outcome of the responding variable is related only to
the manipulated variables.
Separate the substances and apparatus
- Separate the substances and apparatus
- Apparatus : list down the apparatus for the experiment.
Example: Rate of reaction – stop watch
Termochemistry - thermometer
Procedure :
All the steps taken in the procedure must include the apparatus used, quantity and type of substance (powder, solution, lumps
… etc).
No mark is allocated for the diagram. The complete labeled diagram can help students in :
I. Writing the steps taken in the procedure
II. Listing the apparatus and materials

Tabulation of data:
 The number of columns and rows in the table is related to the manipulated and responding
variables
 Units must be written for all the titles in each row and column of the table
 DO NOT WRITE the observation/inference/conclusion in the table.


7.0 THE COMMON COMMAND WORDS IN PAPER 2 & PAPER 3 CHEMISTRY
 The question normally starts with a command word.
 Students must know the meaning of the command word to make sure that the answer given is according to the
question’s requirement.
 Match the command word to the mark allocated for each question.
Command word Explanation/example
Give the name , not the formula.
Name/State the
Example: Name the main element added to copper to form bronze.
name
Wrong answer : Sn.
(paper 2 & 3)
Correct answer : Tin
Give brief answer only. Explanation is not required.
State
Example : State one substance which can conduct electricity in solid state.
(paper 2 & 3)
Answer : Copper
Write what is observed physically.
Example 1 : State one observation when magnesium powder is added to hydrochloric
acid. [ 1 mark]
State the Wrong answer : Hydrogen gas is released.
observation Correct answer : Gas bubbles are released
(Paper 2 & 3) Indicate the change of colour , give the initial and final colour of the substance/chemical.
Example 2: What is the colour change of copper(II) suphate solution. [2 marks]
Wrong answer: The solution becomes colourless
Correct answer : The blue colour of the solution becomes colourless
Give the answer with reasons to explain certain statement / fact / observation/ principal.
Example 1 : Explain why bronze is harder than pure copper [4 marks]
Correct answer :
- Copper atoms in pure copper are all of the same size and ...........1
Explain
- they are arranged in layers that can slide easily when force is applied ...........1
(Paper 2 & 3)
- The presence of tin atoms in bronze that are different in size disturb the
orderly arrangement of atoms in bronze. ...........1
- This reduces the layer of atoms from sliding. ...........1

Give the exact meaning
What is meant by..
Example: What is meant by hydrocarbon.
(Definition)
Wrong answer: A compound that contains carbon and hydrogen
(Paper 2 & 3)
Correct answer: A compound that contains carbon hydrogen only
State the method to conduct the test , observation and conclusion.
Example : Describe how to identify the ion present in the solution . [3 marks]
Describe chemical 3
Answer : - Pour in 2 cm of the solution in a test tube. Add a few drops of sodium
test
hydroxide solution and the test tube is shake the test tube ...........1
(Paper 2 & 3)
- A reddish brown precipitate formed. ...........1
3+
- Fe ions present ………1
State the method to conduct the test observation and conclusion.
Example: Describe the confirmatory test for gas released at the anode (oxygen). [ 3 marks]
Describe gas test. Wrong answer: Test with a glowing wooden splinter.
(Paper 2 & 3) Correct answer: - Place a glowing wooden splinter to the mouth of the test tube ..…….1
- The glowing wooden splinter is lighted up ...……1
- Oxygen gas is released ..…….1

- No mark is awarded for the diagram. The diagram can help students write the steps taken in the
procedure.
Describe an - List of materials 1m
Can be obtained from the diagram
experiment - List of apparatus 1m
( 8 - 10 marks) - Procedure - ( 5 – 8 m)
(Paper 2) - Observation/tabulation of data/ calculation/sketch of the graph/ chemical equation /ionic equation
/conclusion …… etc.
- Any additional details relevant derived from the question.

Answer the question according the requirement :
 Problem statement/Aim of experiment
 Hyphotesis
Plan an  Variables
experiment  List of substances and apparatus
( 17 marks)  Procedure
( Paper 3)  Tabulation of data
Note: For question 3, unlike PEKA report students only need to answer according to what is stated in
the question.
- No mark for the diagram. Diagram can help student writing the steps taken in the procedure.


Describe the
process …
Describe the Give relevant details derived from the question.
structure ….
Describe and write
equation…
Describe how …
(Paper 2 & 3)
Make a prediction for something that might happen based on facts
Predict
Example: Experiment 1 is repeated using a larger beaker. Predict the increase in temperature
(Paper 2 & 3)
Answer : The increase in temperature is lower than experiment 1.
Compare Give the similarities and differences between two items/ situations
(Paper 2)
Give differences between two items/situations
Differentiate
Example : State three differences between ionic and covalent compound.
(Paper 2)
Answer : State three properties of ionic compound and three properties covalent compound
Draw a complete set up of apparatus
Draw a labeled (i) Functional set up of apparatus
diagram of the (ii) Complete label
apparatus (iii) Shade solid, liquid and gas correctly.
(Paper 2) (iv) Draw an arrow and label ’ heat’ if the experiment involves heating
(i)Ionic compound – The number of electrons in each shell is correct, 2 electrons in the first shell
and 8 electrons in the second and third shell.
Draw a diagram to – Show the charge of each particle.
show the bonding – Write the symbol of each element at the centre of the ion.
formed in the (ii) Covalent compound
compound  The number of electrons in each shell is correct, 2 electrons in the first shell and
(Paper 2) 8 electrons in the second and third shell.
 The number of atoms sharing pair of electrons is correct.
 Write the symbol of each element at the center of each atom in the molecule.
Draw graph as follows :
 Label the two axis with the correct unit
 Choose suitable scale, the size of the graph should be at least ¾ of the size of the graph
paper.
Draw graph  Plot all the points correctly
(Paper 3)  Smooth graph ( curve or straight line )
 For the determination of the rate of reaction
(i) Draw a tangent at the curve.
(ii) Draw a triangle at the tangent
Calculate the gradient of the tangent
Draw the energy  Draw an arrow for the vertical axis only and label with energy.
level diagram  Draw two horizontal lines for the reactants and products
( Paper 2)
Draw the  Solid: Draw at least three layers of particles closely packed in orderly manner and they are not
arrangement of overlap.
particles in solid,  Liquid : The particles packed closely but not in orderly manner
liquid and gas.  Gas : The particles are very far apart from each other
(Paper 2)
Draw the direction of
electron flow Draw the direction for the flow of electrons on the circuit, not through the solution.
(Paper 2 /3)
Write chemical  Write the balanced chemical equation
equation  Differentiate :
(Paper 2 & 3) (i) Balanced chemical equation
(ii) Ionic equation
(iii) Half equation for oxidation
(iv) Half equation for reduction
Calculate  Show all the steps taken
(Paper 2 & 3)  Give final answer with unit.
Classify  Draw table to represent the classification.
(Paper 3)


CHEMISTRY PERFECT SCORE MODULE

SET 
1. The Structure of Atom
2. Chemical Formulae and Equations
3. Periodic Table of Elements
4. Chemical Bonds


PAPER 2 : SECTION A [STRUCTURE]

1 Diagram 1 shows the apparatus set-up used in an experiment to determine the empirical formula of an
oxide of copper.
Copper oxide

Burning of excess
hydrogen
Dry hydrogen
gas

Heat
DIAGRAM 1
The following data was obtained:
Mass of combustion tube + porcelain dish = 25.30 g
Mass of combustion tube + porcelain dish + copper(II) oxide = 53.30 g
Mass of combustion tube + porcelain dish + copper = 47.70 g

(a) What is meant by empirical formula?
..............................................................................................................................................................

………………………………………………………………………………………………………..
[1 mark]
(b) Write a chemical equation for the reaction used to produce hydrogen gas.
……......................................................................................................................................................
[2 marks]
(c) How to ensure that all the copper oxide is completely reacted?

……………………………………………………………………………………………………......

………...………………………………………………………………………………………..........
[1 mark]
(d) Based on the data given, determine the empirical formula of the copper oxide.

[4 marks]
(e) Write the chemical equation for the reaction between hydrogen and the oxide of copper.
……………..........................................................................................................................................
[2 marks]
(f) After the reaction is completed, hydrogen gas is allowed to flow continuously until the copper
is cooled to room temperature. Explain why .

………….………………………………………………………………………………………….....

………….………………………………………………………………………………………….....
[1 marks]


(g) The empirical formula for magnesium oxide can be determined by direct heating of
magnesium.
Draw a labeled diagram to show apparatus set-up to carry out this experiment.

[ 2 marks]

2 (a) 70.2 g of aluminium carbonate decomposed easily when heated to produce aluminium oxide based
on the following equation.

................(s) → Al2O3(s) + CO2(g)

[Relative atomic mass: Al: 27 ; C: 12; O: 16; 1 mole of gas occupied 24 dm3 at room condition]

(i) Write the formula of Aluminium carbonate.

…………..…………………………………………………………………………………...
[1 mark]
(ii) Write a balanced chemical equation for the reaction above.

…………………………………………………………………............................................
[2 marks]
(iii) Calculate the mass of aluminium oxide that is produced.

[3 marks]

(iv) Calculate the volume of carbon dioxide gas produced at room conditions .

[3 marks]


(b) Table 2 shows an experiment to investigate the effect of heat on metal carbonate.

Diagram Procedure Observation

Metal carbonate is heated White solid turns yellow
Metal
and the gas produced is when hot and white
carbonate passed through lime water. when cool.
The lime water turns
Heat
cloudy.
Lime water

Table 2

Based on the experiment:

(i) Name the metal carbonate used.

……….....................................................................................................................................
[1 mark]
(ii) State the name of the products formed.

……….……………………………………………………………………………………...
[1 mark]
(iii) Write a chemical equation for the reaction.

…….……………………………………………………………………………..................
[2 marks]
3 Table 3 shows the proton number and the number of neutrons for atoms P, Q, R and S.

Atom Proton number Number of neutrons
P 3 4
Q 16 17
R 16 16
S 19 20
Table 3
(a) (i) What is meant by the proton number?

………………………………………………………………………………………….....
[1 mark]
(ii) What is the nucleon number of atom P?

…………….……………………………………………………………………………..............
[1 mark]
A
(b) Write the symbol for atom Q in the form Z
X
..………….………………………………………………………………………………………
[1 mark]
(c) Which atoms have the same number of valence electrons?

……………………………………………………………………………………………………
[1 mark]


(d) (i) Which atoms are isotopes?

……………………………………………………………………………..................................
[1 mark]
(ii) State a reason for your answer in (d) (i).

……………………………………………………………………………..................................
[1 mark]

(e) Diagram 3 shows a graph of temperature against time of substance X when it is heated until it
boils.

Temperature /oC

F

D E
777

B C
63

A
Time /s
t1 t2 t3 t4
Diagram 3

(i) What is the melting point of substance X?

……….………………………………………………………………………………
[1 mark]
(ii) Complete the table below by stating the physical state of substance X at the section AB
and DE.

Section Physical state
AB

DE
[1 mark]
(iii) Explain why the temperature remains constant from t1 to t2.

………………………………………………………………………………………

…………………………………………………………………………………………
[2 marks]


4 Table 4 shows the proton number of a few elements in Period 3.

Element Sodium Magnesium Aluminium Chlorine Argon

Proton number 11 12 13 17 18
Table 4

Based on Table 4, answer the following questions:

(a) State two elements which are metals.

…………………………………………………………………………………………………
[1 mark]
(b) Chlorine is in Group 17 in the Periodic Table of Elements. What is another name for group 17?

…………….……………………………………………………………………………………
[1 mark]
(c) Write the electron arrangement of aluminium atom.

………………………………………………………………………………………………………..
[1 mark]
(d) (i) Arrange the element in Table 4 according to descending order of atomic sizes
.
…………………………………………………………………………………….
[1 mark]
(ii) Explain your answer in (d) (i).

………………………………………………………………………………………

………………………………………………………………………………………
[2 marks]
(e) When sodium is burnt in chlorine gas, sodium chloride is formed.

(i) State one observation for the reaction.

…………………………………………………………………………………………
[1 mark]
(ii) Write the chemical equation for the reaction.

…………………………………………………………………………………………
[2 marks]
(iii) State one physical property of sodium chloride.

…………………………………………………………………………………………
[1 mark]


5 Diagram 5 shows the symbols of atom of elements U, V, W and X.
7 12 19 20
3 U 6 V 9 W 10 X
Diagram 5

(a) (i) Which element is an inert gas?

.....................................................................................................................................................

[1 mark]
(ii) Give a reason for your answer in (a) (i).

.....................................................................................................................................................
[1 mark]
(b) Element W exists as diatomic molecule.
State the type of chemical bond in molecule W.

...........................................................................................................................................................
[1 mark]
(c) Element V can react with element W to form a compound.
(i) Write the chemical formula for the compound formed.

..............................................................................................................................................
[1 mark]
(ii) Draw the electron arrangement for the compound formed.

[2 marks]
(iii) State one physical property for the compound formed.

.....................................................................................................................................................
[1 mark]
(d) Element U reacts with element W to form a compound .

(i) State the type of the compound produced.

.....................................................................................................................................................
[1 mark]
(ii) Explain briefly how the compound is formed.
.....................................................................................................................................................

.....................................................................................................................................................

.....................................................................................................................................................

[3 marks]
(iii) Draw the electron arrangement for the compound formed.

[2 marks]

PAPER 2: SECTION B [ESSAY]

6 (a) Diagram 6.1 shows the electron arrangement for atom of an element from Group 17 in the
Periodic Table of Element.

Diagram 6.1
Based on Diagram 6.1,
(i) Write the electron arrangement for the atom and state the name of the element.
[2 marks]
(ii) Write a chemical equation for the reaction between the element and iron.
[2 marks]
(b) Table 7.2 shows the observation of the reaction between Group 1 elements X , Y and Z with
water.

Group I element Observation

X X moves slowly on the water surface with a soft ‘hiss’ sound.
[Proton number =3] A colourless solution that turns red litmus paper blue is formed.
Y moves rapidly and randomly on the water surface with a ‘hiss’
Y
sound. A colourless solution that turns red litmus paper blue is
[Proton number =11]
formed..
Z burns with a reddish-purple flame, moves very rapidly and
Z
randomly on the water surface with ‘hiss’ and ‘pop’ sound. A
[Proton number =19]
colourless solution that turns red litmus paper blue is formed..
Table 6.2
Based on Table 6.2

(i) Arrange X, Y and Z in descending order of reactivity of Group I elements towards water.
Compare and explain the reactivity X and Z with water.
[6 marks]

(ii) Compare the chemical property of X, Y and Z. Give a reason for your answer.
[2 marks]
(c) Diagram 6.3 shows the electron arrangement of a molecule XY2.

Y X Y

Diagram 6.3
Based on Diagram 6.3, write the electron arrangement for atom element X and element Y.
Explain briefly how the molecule is formed from atom X and atom Y.
Explain the position of element Y in the Period Table of Element.

[8 marks]


7. Table 7.1 shows the electron arrangement for atoms W, X and Y. These letters are not the actual symbols of
the elements.
Element Electron arrangement
W 2.4
X 2.8.7
Y 2.8.8.1

Table 7.1
(a) State the position of element X in the Periodic Table of Elements.
Explain how you determine the group and the period of element X.

[4 marks]
(b) Atoms W and Y can form chemical bonds with atom X.
Explain how the bond is formed between :

(i) Atoms Y and X
(ii) Atoms W and X

[10 marks]
(c) Table 7.2 shows physical property of compound P and compound Q.

Physical Property Compound P Compound Q
Melting point High Low
Cannot conduct
Can conduct electricity in
Electrical conductivity electricity in molten and
molten state or aqueous solution
solid states

Table 7.2
State the type of bond in compound P and compound Q.
By choosing one physical property, explain why there is a difference between the property
of the compounds.

[6 marks]
PAPER 2 SECTION C: ESSAY
8 (a) Diagram 8 shows the apparatus set up to determine the empirical formula of oxide of metal M. M
is less reactive than hydrogen.
Thistle funnel
Oxide of metal M

Dry hydrogen gas

Heat
Dilute acid Metal N
R

Diagram 8
(i) Name a suitable dilute acid and metal N that are used to prepare hydrogen gas.
[2 marks]
(iii) Suggest a suitable chemical substance for R and state the function of R.
[2 marks]
(iv) State the example of oxide of metal M. Describe the redoxs reaction that occurs in the combustion
tube based on the changes in oxidation number.
[6 marks]

(b) The information below is about hydrocarbon Y

 Empirical formula of Y is CH2
 Molar mass of Y = 56 gmol-1

(i) Determine the molecular formula for hydrocarbon Y.
[Relative atomic mass of C =12 , H = 1 ]
[2 marks]

(ii) Describe an experiment to prepare hydrocarbon Y in the laboratory from its corresponding
alcohol.
In your answer, include the diagram of the appratus set-up, materials used, and
procedure.
[8 marks]
9 (a) (i) What is meant by empirical formula?
[1 mark]

(ii) Diagram 9.1 shows the apparatus set-up used to determine the empirical formula of oxide
of metal X.
Oxide of metal X

Dry hydrogen gas
→

Heat

Diagram 9.1

Suggest one suitable oxide of metal X.
Write a balanced chemical equation involved.
[3 marks]

(b) Diagram 9.2 shows the apparatus set-up used to determine the empirical formula of another oxide of metal.

Metal

Heat

Diagram 9.2
(h) Suggest one suitable oxide of the metal.
[1 mark]
(ii) Based one diagram 9.2, describe how you could determine the empirical formula of the named metal oxide
in the laboratory. Your description should include
- procedure of experiment
- tabulation of results
- calculation of the empirical formula
[10 marks]

(c) A carbon compound contains 84.6% of carbon and 15.4% of hydrogen by mass.
The relative molecular mass of this compound is 70. Calculate the molecular formula of this compound.
[Relative atomic mass: C, 12; H, 1]
[5 marks]



SET 

1. Electrochemistry
2. Oxidation and Reduction


PAPER 2: SECTION A [STRUCTURE]

1 Diagram 1 shows the apparatus set- up for the combination of electrolytic cell and chemical cell.

V

Magnesium Copper electrode
electrode

Copper(II) sulphate
solution

Cell I Cell II

Diagram 1
(a) Which cell is the electrolytic cell?

……………………………………………………………………………………..……….………..
[1 mark]
(b) Based on Cell I

(i) State the negatif terminal of the cell .

…………..…………………………………………………………………………………...
[1 mark]
(ii) Draw the flow of electron in Diagram 1.
[1 mark]
(iii) State the observation at copper electrode.

………………………………………………………………………………………………
[1 mark]
(c) Write half equation for the reaction at copper electrode.

…………..………………………………………………………………………………………...….
[2 marks]
(d) Based on the Cell II
(i) State the energy change in the cell.

………………………………………………………………………………….……………
[1 mark]
(ii) What can be observe at the copper(II) sulphate solution?

….……………………………………………………………………………………………
[1 mark]
(iii) Explain your answer in d(ii)

……………………………………………………………………..………….……………..
[2 marks]


2 (a) Diagram 2.1 shows the apparatus set-up to investigate the transfer of electrons at a distance
between potassium iodide solution and acidified potassium manganate(VII) solution.

Diagram 2.1
(i) Name the product formed at electrode R.

..……….…………...................................................................................................................
[1 mark]
(ii) Complete the half equation for the reaction at electrode S.

MnO4 - + ........ H+ + ....... e → Mn2+ + ............... H2O
[1 mark]
(iii) State the change in oxidation number of manganese and name the process that occurs at S.

Change in oxidation number : ……………..........…………………………...........………...

Name of process : .................................................................................................................
[2 marks]
(iv) Suggest a substance that can replace potassium iodide solution in order to obtain the same
reaction.

…………..............................................................................................................................
[1 mark]
(b) Diagram 2.2 shows the set up of the apparatus to investigate the reactivity of metals J, K and L.
The different metals are heated consecutively.

Diagram 2.2


Table 2.2 shows the observation of the experiment.

Colour of residue
Metal Observations
Hot Cold
J Burns brightly Yellow White
K Glows dimly Black Black

L Burns with a very bright flame White White

Table 2.2
(i) State the name of metal J.

……….. ………......................................................................................................................
[1 mark]
(ii) Write a chemical equation for the reaction between metal J and oxygen.

……….……………................................................................................................................
[2 marks]
(iii) Based on the observation in Table 2.1, arrange metals J, K and L in ascending order of
reactivity towards oxygen.

……….. .…….........................................................................................................................
[1 mark]
(iv) A mixture of metal J and oxide of metal L is heated strongly.
Predict an observation. Give a reason.

. ………....................................................................................................................................

……….. ..................................................................................................................................
[2 marks]


PAPER 2: SECTION B [ESSAY]

3 (a) Table 3.1 shows the electrical conductivity of two different compounds

Compound Electrical conductivity
Propanone (C3H6O) Cannot conduct electricity
Sodium chloride solution (NaCl) Conduct electricity

Table 3.1

Referring to Table 3.1, explain why there is a difference in the electrical conductivity.
[4 marks]

(b) Diagram 3.1 shows two types of cells.

V

A B Copper plate C D Zinc plate

Copper(II) sulphate
solution

Cell X Cell Y
Diagram 3.1
Compare and contrast cell X and cell Y. Include in your answer the observations and half
equations for the reactions at the electrodes in both cells.
[8 marks]
(c) An experiment is carried out to determine the position of metals silver, L and M in the
electrochemical series. Diagram 3.2 shows the results of the experiment.
I II III

Silver nitrate Silver nitrate L nitrate
solution solution solution
Experimen

L M M

 Grey solid deposited
Observation  Grey solid deposited  No change
 Light blue solution
 Colourless solution

Diagram 3.2


(i) Based on the results in Diagram 3.2, arrange the electroposivity of metals silver, L and M in ascending
order.
Explain your answer.
[7 marks]
(ii) Based on observation in experimen II, suggest one possible metal for M
[1 mark]

4 (a) The following is the chemical equation of a redoxs reaction

Zn + Pb(NO3)2 → Zn(NO3)2 + Pb

Referring to the above chemical equation,

(i) Write half equation for the oxidation and the reduction reactions.
[4 marks]
(ii) Identify substance that is oxidized and reduced. Explain your answer in term of transfer of
electrons.
[4 marks]

(b) Diagram 4 shows two redox reactions that take place in test tubes P and Q.

Chlorine water

Iron (II) sulphate Potassium iodide

Test tube P Test tube Q
Diagram 4

(i) State the observations and write the ionic equation for the reaction in test tubes P and Q
respectively.
[6 marks]

(ii) State the name of the product formed in each test tube P and Q
[4 marks]
(iii) Describe a confirmation test to verify the product in test tube Q
[2 marks]


PAPER 2: SECTION C [ESSAY]

5 (a) Diagram 5 shows the apparatus set-up and observations for experiments 1 using 1.0 moldm-3
aqueous solution of compound XSO4 and experiment II using 0.0001 moldm-3 aqueous solution of
compound XY2.

Experiment Apparatus set-up Observation

Cathode:
Brown solid deposited

I

Anode:
A colorless gas is produced.

Cathode:
Brown solid deposited

II
Anode:
A colorless gas is produced.
The gas relight a glowing splinter.

Diagram 5

(i) In both experiment I and experiment II, the product formed at cathode is the same. Using
your knowledge of factors affecting the selective discharge of ions at the electrodes,
- suggest one possible cation for X2+ ion
- write the half equation for the reaction at the cathode
- state the name of the product at cathode
[4 marks]

(ii) Name the product formed at anode in experiment I. Describe a confirmatory test to identify the
gas produced.
[3 marks]

(iii) Suggest one possible anion for Y- ion in experiment II.
Name the product at the anode and explain the formation of the product in the experiment.
[6 marks]
(b) Pure copper metal is used to make copper wire.
Describe how to purify the copper metal using an electrolysis process.
Include a labelled diagram in your answer.
[7 marks]


6 (a) Diagram 6.1 shows the apparatus set-up to study the effect of metals P and Q on the rusting of iron
nail. The results are recorded after three days.

Experiment Observation after 3 days

Agar-agar solution with potassium
hexacyanoferrate(III) and
phenolphthalein solution.  Dark blue precipitate
 Iron nail rust
I

Iron nail wrapped with metal P

Agar-agar solution with potassium
hexacyanoferrate(III) and
phenolphthalein solution.
 Solution turns pink.
 Iron nail does not rust
II

Iron nail wrapped with metal Q

Diagram 6.1

(i) Name one possible metal for metal P and metal Q
[2 marks]
(ii) Explain why there is a difference in observation in Experiment I and II.
[8 marks]

(b) Diagram 6.2 shows a redox reaction between bromine water and iron(II) sulphate solution.

Diagram 6.2

(i) Describe the redox reaction that occur in the test tube. Your answer should include the ionic
equation and observations.
[8 marks]

(ii) Based on the oxidation reaction in (b) (i), describe a chemical test to identify the product formed
in the test tube.
[2 marks]



SET 
1. Acids and Bases
2. Salts
3. Rate of reaction
4. Thermochemistry


PAPER 2 SECTION A [STRUCTURE]
1. Diagram 1 shows four test tubes labeled A,B,C and D which are used to study the relationship between
pH value of acid and alkali with the molarity.
pH paper

A B C D
5 cm3 HCl 5 cm3 HCl 5 cm3 NaOH 5 cm3 NaOH
0.1 mol dm-3 0.01 mol dm-3 0.1 mol dm-3 0.01 moldm-3
Diagram 1
(a) Determine which solution has
(i) highest pH value?

…………….……………………………………………………………………………........
[1 mark]
(ii) lowest pH value?

……………………………………………………………………………………….............
[1 mark]

(b) If the hydrochloric acid in test tube B is replaced with 5 cm3 of 0 .1 mol dm-3 ethanoic acid,
predict the pH value of the solution. Explain your answer

…………………………………………………………………………………………………………...………..

…. ……………………………………………………………………………………………………

……………………………………………………………………………………………………….
[3 marks]

(c) Excess of magnesium powder is added to 5 cm3 of 0.1moldm-3 hydrochloric acid in test tube A
(i) Name the products formed.
.
……...………………………………………………………………………………………..
[1 mark]
(ii) Write an ionic equation for the reaction in test tube A

………………………………………………………………………………………………
[1 mark]
(iii) Calculate volume of hydrogen gas released at room conditions in test tube A
[1 mol of gas occupies 24 dm3 at room conditions]

[3 marks]


(d) If the solution in test tube C is added to lead(II) nitrate solution. State the observation from the
reaction.

…….………………………………………………………………………………………………….
[1 mark]

2. (a) Diagram 2.1 shows the pH value of glacial ethanoic acid in solvent P and solvent Q respectively.

4.8 7.0

Glacial ethanoic acid Glacial ethanoic acid +
+ solvent P solvent Q

Diagram 2.1

(i) Give one example of each solvent P and solvent Q.

Solvent P: ………………………………………………………….………...………………

Solvent Q: ………………………………………………………………………………….
[2 marks]

(ii) If magnesium ribbon is added into beaker containing glacial ethanoic acid and solvent P,
what can be observed?

……………………………………….………………………………………………………
[1 mark]
(iii) Explain why ethanoic acid in solvent P and solvent Q has different the pH value.

….……………………………………………………………………………………………

….……………………………………………………………………………………………

….……………………………………………………………………………………………

...……………………………………………………………………………………………..
[3 marks]

(b) Diagram 2.2 shows the concentration of hydrochloric acid decrease when water is added into
beaker J.

Add water
250 cm3 of 0.04 moldm-3
100 cm3 of 0.5 moldm-3
hydrochloric acid
hydrochloric acid

Beaker J Beaker L
Diagram 2.2


(i) When water is added into beaker J, what happen to the pH value of the hydrochloric acid?
Give reason to your answer.

….……………………………………………………………………………………………

.………………………………………………………………………………………………
[2 marks]

(ii) Calculate the volume of hydrochloric acid in beaker J that is needed to prepare
hydrochloric acid in beaker L.

[2 marks]
3. A student carried out an experiment to investigate the properties of three solutions. Table 3 shows the results
of the experiments.

Test tube P Q R
Set-up of
Red litmus Red litmus Magnesium
apparatus
Paper Paper

Ammonia gas Ammonia gas Hydrogen
dissolved in dissolved in chloride gas
water propanone dissolved in water

Observation The red litmus
paper turned blue.

Table 3
(a) What is meant by strong alkali?

.......................................................................................................................................
[1 mark]
(b) What is the property of the solution in test tube P?

.......................................................................................................................................
[1 mark]
(c) What are the types of particles that exist in the test tubes P and Q?

Particles in the test tube P: ..........................................................................................

Particles in the test tube Q: .........................................................................................
[ 2 marks]

(d) Is there any changes of colour of the litmus paper in test tube Q? Explain why.

......................................................................................................................................

......................................................................................................................................
[ 2 marks]


(e) (i) What can be observed in test tube R?

.......................................................................................................................................
[1 mark]
(ii) Write a chemical equation for the reaction in test tube R.

.......................................................................................................................................
[2 mark]

(iii) 2.4 g of magnesium is reacted completely with the solution in test tube R.
Calculate the volume of the hydrogen gas produced at room condition
[Relative atomic mass: Mg,24; 1 mol of gas occupies 24 dm3 at room conditions]

[ 2 marks]

4. Diagram 4 shows a series reaction of copper compound.

Copper(II) Sodium carbonate Copper(II) Copper(II) oxide
nitrate carbonate

Copper(II) sulphate

Diagram 4
a) Copper(II) nitrate solution reacts with sodium carbonate solution to form copper(II) carbonate precipitate.
(i) What is the colour of Copper(II) carbonate?

……………………………………………………………………………………………….............
[1 mark]
(ii) Name the reaction.

.............................................................................................................................................................
[1 mark]
b) Heating of copper(II) carbonate produces copper(II) oxide and gas R.
i) Name gas R.
………………………………………………………………………………………………..
[1 mark]
ii) Write the chemical equation of the reaction.

......................................................………………………………………………………......................
[2 marks]


(iii) Draw a labeled diagram for the heating of copper(II) carbonate to produce copper(II) oxide and
gas R. In your diagram show how gas R is tested.

[2 marks]
c) Copper(II) carbonate reacts with hydrochloric acid to produce copper(II) chloride. The chemical
equation is shown below.
CuCO3 + 2HCl → CuCl2 + CO2 + H2O
12.4 g copper(II) carbonate reacts completely with excess hydrochloric acid.
Calculate the mass of copper(II) chloride.
[Relative atomic mass: Cu = 64, C = 12, O=16 , Cl = 35.5, H=1)

[2 marks]

5. Three experiments were conducted to investigate the factors affecting the rate of reaction. The results are
shown in the Table 5
Experiment Reactants Temperature / 0C Time taken for all the
magnesium to dissolve/s
0.4g magnesium ribbon and 50 cm3
I 1 moldm-3 hydrochloric acid 30 100

II 0.4g magnesium powder and 50 cm3 60
1 moldm-3 hydrochloric acid 30

0.4g magnesium ribbon and 50 cm3
III 1 moldm-3 hydrochloric acid and copper(II) 30 45
sulphate solution
Table 5
(a) Write a chemical equation to show the reaction between magnesium and hydrochloric acid.

………..………………………………………………………………………………………………
[2 marks]
(b) Calculate the number of mole of
[Relative atomic mass of Mg = 24]
(i) Magnesium

[1 mark]
(ii) Hydrochloric acid

[1 mark]

(c) If hydrochloric acid used is excess, calculate the maximum volume of hydrogen gas produce at
room temperature and pressure.
[1 mole of gas occupies the volume of 24 dm3 at room temperature and pressure]

[2 marks]

(d) Calculate the average rate of reaction for Experiment I and II.

[2 marks]
(e) What is the purpose of using copper(II) sulphate?

……………….………………………………………………………………………………………
[1 mark]
(f) The factor that affects the rate of reaction in this experiment is total surface area and the use of
catalyst. State two other factors that affect the rate reaction in this experiment.

………………………………………………………………………………………………………

……..………………………………………………………………………………………………..
[2 marks]

6. An experiment is carried out to determine the heat of displacement for the reaction between copper(II)

sulphate solution and excess zinc powder. 50.0 cm3 of 0.5 mol dm 3 copper(II) sulphate solution is poured into
a plastic cup. The initial temperature of the solution is recorded after 5 minutes. 5 g of excess zinc powder is
added into a plastic cup. The mixture is stirred and the highest temperature is recorded.
The following data is obtained:

Initial temperature of copper(II) sulphate solution = 28.0 0C
Highest temperature of the mixture reached = 38.0 0C

[Relative atomic mass : Cu,64; S,32; O,16; Zn, 65; Specific heat capacity of water : 4.2 Jg1 0C1]

(a) Based on the experiment, what is meant by the heat of displacement?

………………….……………………………...…………………………………………………….
[1 mark]
(b) Write an ionic equation for the reaction.

………………………………………………………………………………………………………..
[1 mark]
(c) State two observations in the experiment.

(i) …………………………………………………………………………………………….…...…

(ii) ………………………………………………………………………………………………......
[2 marks]

(d) Calculate,
(i) the heat released

[1 mark]
(ii) the number of moles of copper (II) sulphate reacted

[1 mark]


(iii) the heat of displacement

[2 marks]
(e) Why excess zinc powder is used in this experiment?

……...………………………………………………………..……………………………………….
[1 mark]
(f) Draw the energy level diagram for the reaction.

[2 mark]
7. 50 cm3 1.0 mol dm-3 sodium hydroxide solution is poured into a polystyrene cup. The polystyrene cup is
then placed into a beaker as shown in Diagram 5

Beaker Polystyrene cup

Sodium hydroxide solution +
hydrochloric acid

Diagram 5

The initial temperature of sodium hydroxide solution in the polystyrene cup is measured. 10 cm3 of
hydrochloric acid is added to the 50 cm3 sodium hydroxide and the temperature increase is recorded. Then,
the heat energy released is calculated. The experiment is repeated by adding different volumes of
hydrochloric to the 50 cm3 of sodium hydroxide. The results are tabulated as shown below.

Volume of sodium hydroxide Volume of hydrochloric acid Heat energy released / kJ
solution / cm3 added / cm3
50 10 1.1
50 20 2.2
50 30 3.4
50 40 4.5
50 50 5.6
50 60 5.6
50 70 5.6

(a) Plot a graph heat energy released against volume of hydrochloric acid added.
[3 marks]

(b) (i) Based on the graph, determine the volume of hydrochloric required for complete
neutralisation with 50 cm3 1.0 mol dm-3 sodium hydroxide
[1 mark]

(ii) From your answer in (b) (i), calculate the concentration of hydrochloric acid used
in moldm-3.
[2 marks]

(c) Why the content in the polystyrene cup has to be stirred continuously throughout the
experiment?

………………………………………………………………………………………………………..
[1 mark]

(d) Explain briefly why the heat released becomes constant after 50 cm3 of hydrochloric acid is
added.

………………………………………………………………………………………………………

……………………………………………………………………………………………...............
[1 mark]
(e) (i) Calculate the heat energy released when 1 mole of sodium hydroxide is neutralized
by hydrochloric acid.

[1 mark]
(ii) Draw the energy level diagram for the reaction that occurred in the polystyrene cup.

[2 marks]
(f) In another experiment, 50 cm3 1.0 mol dm-3 sodium hydroxide solution is added with 50 cm3 1.0
mol dm-3 ethanoic acid.

(i) Predict the heat energy released

……………………………………………………………………………………………….
[1 mark]
(ii) Give a reason for your answer in (f) (i).

………………………………………………………………………………………………

………………………………………………………………………………………………

………………………………………………………………………………………………
[2 marks]


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