Name : _________________________ (
)
Class : __________
SMJK PEREMPUAN CHINA PULAU PINANG
CHEMISTRY FORM 5
PAPER 2
SPM TRIAL EXAMINATION 2013
2 ½ HOURS
INSTRUCTIONS:
1. Read the questions carefully.
2. Answer all the questions in Section A.
3. Answer only ONE question in Section B.
4. Answer only ONE question in Section C.
Section
Question
Full marks
1
10
2
10
3
10
4
10
5
10
6
10
7
20
8
20
9
20
10
20
Marks
A
B
C
TOTAL
1
Section A
[60 marks]
Answer ALL questions in this section.
1. Diagram 1 shows the electron arrangement for the atom of three elements, P,Q and
R.
Diagram1
(a) Write the electron arrangement for the atoms of elements P, Q and R. [1m]
P:................................................Q:..............................................R:.....................................
(b) State the group and period in the Periodic Table for each of the elements. [3m]
Element
P
Q
R
Group
Period
(c) (i) Which element is chemically inert? [1m]
...............................................................................................................................................
(ii) Give a reason for your answer in (c)(i). [1m]
...............................................................................................................................................
(d) Element Q dissolves in water to form an acidic solution and a bleaching agent. Write
the chemical equation for the reaction of Q with water. [1m]
...............................................................................................................................................
(e) Which element reacts actively with water? [1m]
...............................................................................................................................................
(f) The proton number for element X is 17. Among P, Q and R which element shows
similar chemical properties to X? [1m]
...............................................................................................................................................
(g) Arrange the atoms P,Q and R in order of increasing atomic size. [1m]
.............................................................................................................................................
2. Diagram 2 shows the energy level diagram for the reaction between 0.5 g of zinc
powder and 25 cm3 of 0.2 moldm-3 copper(II) nitrate solution.
2
Diagram 2
(a) State two observations for this reaction. [2m]
…………………………………………………………………………………………
………………………………………………………………………………………….
(b) Write the ionic equation for the reaction. [1m]
…………………………………………………………………………………………
(c) Calculate the number of moles of copper(II) nitrate in the solution. [1m]
(d) Calculate the mass of copper formed. [Relative atomic mass: Cu,64]
(e) Calculate the heat energy released during this reaction.
[1m]
[2m]
[Density of water: 1.0 gcm ; Specific heat of capacity of water : 4.2 Jg-1 ˚C-1 ]
-3
(f) Calculate the rise in the temperature of the mixture solution. [1m]
3
(g) If the experiment is repeated by using 0.5 g of zinc powder and 50 cm3 of
0.2 moldm-3 copper(II) nitrate solution. Predict the rise in temperature of the mixture
solution. Explain your answer. [2m]
…………………………………………………………………………………………
…………………………………………………………………………………………
…………………………………………………………………………………………
3. Diagram 3 shows a series of reactions.
Butan-1-ol
X
Butanoic acid
A
But-2-ene
B
Substance P
Y
2,3-dibromobutane
Diagram 3
(a) Write the molecular formula for butan-1-ol. [1m]
…………………………………………………………………………………
(b) How is reaction A is performed in the laboratory? [2m]
……………………………………………………………………………………
……………………………………………………………………………………
(c) (i) Name reaction X. [1m] ……………………………………………………..
(ii) Write the chemical equation for reaction X. [1m]
………………………………………………………………………………….
(d) (i) Name the substance needed in reaction Y. [1m]
……………………………………………………………………………………
(ii) Name reaction Y. [1m] ………………………………………………………
(e) Draw the structural formula for 2,3-dibromobutane. [1m]
(f) Reaction B is a hydrogenation process. Identify substance P and the type of
catalyst used. [2m]
P: ……………………………………………………………………………….
4
Catalyst: ……………………………………………………………………….
4. Acid Z is an organic acid with the formula C4H6O4. A student prepared two
0.1 mol dm-3 solutions of acid Z, one in water and the other in dry propanone. Both
the acid solutions are used in tests as described in Table 1.
0.1 moldm-3 acid Z in water
Tests
A small piece of calcium
carbonate is added
A universal indicator is
dipped into the solution
Effervescence occurs. A gas
that turns lime water chalky
evolved.
The universal indicator turns
red with a pH of 3
Table 1
0.1 moldm-3 acid Z in dry
propanone
No visible change.
Unchanged with a pH of 7
(a) Calculate the mass of acid Z required to prepare 250cm3 0.1 moldm-3 of acid Z.
[Relative atomic mass: H,1 ; C,12 ; O,16]
[2m]
(b) Explain why the solution of acid Z in water reacts with calcium carbonate but does
not in dry propanone.
[2m]
……………………………………………………………………………………
……………………………………………………………………………………
……………………………………………………………………………………
(c) What type of acid Z particles exist in dry propanone? [1m]
…………………....................................................................................................
(d) In a separate experiment, the student transfers 50.0 cm3 0.1 moldm-3 of acid Z into a
conical flask followed by a few drops of phenolphthalein. 20.0 cm3 of 0.5 moldm-3
sodium hydroxide solution is needed to completely neutralise the acid.
(i) Calculate the number of moles of acid Z used in the experiment. [1m]
(ii) Calculate the number of moles of sodium hydroxide used in the experiment. [1m]
5
(iii) How many moles of sodium hydroxide are required to completely reacts with 1 mole
of acid Z?
[1m]
(iv) What is the basicity of acid Z? [1m]
…………………………………………….
(v) Write a chemical equation for the reaction between acid Z and sodium hydroxide.
………………………………………………………………………………………..[1m]
5. Diagram 4 shows a series of reactions involving compound P. When P is heated, it
decomposes into residue Q which is black in colour, a brown gas R and colourless gas
S which ignites a glowing wooden splinter.
Diagram 4
(a) Name
(i) Compound P: …………………………..
(ii) Gas R: …………………………………
(iii) Residue Q: …………………………… [3m]
(b) Write a balanced chemical equation for the thermal decomposition of compound P.
……………………………………………………………………………………….. [1m]
(c) (i) Name the reaction I. [1m]……………………………………………………..
(ii) Name solution X. [1m] ………………………………………………………
6
(d) (i) Write a balanced chemical equation for reaction II. [1m]
……………………………………………………………………………………...
(ii) Name reaction II. [1m] …………………………………………………………
(e) Predict the observation when excess ammonia solution is added to solution X. [1m]
…………………………………………………………………………………………..
(f) Write an ionic equation for the formation of blue precipitate Y. [1m]
……………………………………………………………………………………………
6. Diagram 5 shows an experiment set up to investigate the reaction between potassium
iodide solution and iron(III) sulphate solution through the transfer of electron at a
distance.
Diagram 5
(a) (i) What is the function of the dilute sulphuric acid in Diagram 5. [1m]
……………………………………………………………………………………
(ii) Name a substance that can replace the dilute sulphuric acid. [1m]
…………………………………………………………………………………….
(b) How do you know that the reaction has started?[1m]
…………………………………………………………………………………….
(c) (i) What change in colour is observed around electrode P? [1m]
………………………………………………………………………………….....
(ii) Give a chemical test to confirm the product at electrode P. [1m]
……………………………………………………………………………………...
(d) Name the reaction which has occurred around electrode Q. [1m]
……………………………………………………………………………………...
(e) Write an ionic equation to represent the reaction occurred..
(i) around electrode P. [1m]
………………………………………………………………………………......
(ii)around electrode Q. [1m]
7
………………………………………………………………………………......
(f) Name the oxidizing agent in this reaction. [1m]
……………………………………………………………………………………...
(g) Suggest another reagent that can replace iron(III) sulphate solution. [1m]
……………………………………………………………………………………...
Section B
[20 marks]
Answer any ONE question from this section.
7. (a) (i) Based on Diagram 6, explain the rusting of iron in terms of a redox reaction.
[7m]
(ii)Explain how galvanization can prevent rusting. [3m]
(b) The following chemical equation represents an oxidation-reduction reaction.
Cl2 + 2KBr  2KCl + Br2
Based on the equation given above,
(i) Define oxidation and reduction in terms of the change in the oxidation number.
(ii) Name the compounds that undergo oxidation and reduction.
(iii) State the change in the oxidation number of each element that you have
named in (b)(ii).
(iv) Name the oxidizing agent and reducing agent.
(v) Write equations for the half reactions of reduction and oxidation.
[10m]
8. Three experiments, I, II and III are carried out to investigate the factors affecting the
rate of reaction. Table 2 shows the reactants and the conditions of reaction involved.
Experiment
Reactants
Condition of
reaction
8
I
II
III
Excess zinc
Excess zinc
Excess zinc
50 cm3 of 0.5 mol dm-3 hydrochloric acid
50 cm3 of 0.5 mol dm-3sulphuric acid
50 cm3 of 0.5 mol dm-3sulphuric acid
Table 2
Room temperature
Room temperature
60˚C
(a) (i) Referring to experiments I, II and III, state:

The meaning of rate of reaction,

Two factors that affect the rate of reaction.
[3m]
(ii) Write a balanced chemical equation for the reaction in experiment I.
[2m]
(b) Calculate the total volume of hydrogen gas released in experiment I.
[Molar volume of gas at room conditions is 24 dm3]
[3m]
(c) Diagram 7 shows the results of experiments I, II and III.
Diagram 7
Based on the graph,
(i) Compare the rate of reaction between experiment I and experiment II.
Explain your answer using the Collision Theory.
[5m]
(ii) Suggest one way to obtain curve III without changing the zinc, acid or
temperature in experiment II. Explain your answer using the Collision
Theory.
[5m]
(iii) Explain why the total volume of hydrogen gas released in experiment II is
doubled that of experiment I.
[2m]
Section C
[20 marks]
Answer any ONEquestion from this section.
9
9. Carbon compound can be classified into hydrocarbons and non-hydrocarbons.
(a) Pentane and pentene are hydrocarbons. Table 3(a) shows the observations of a
test to differentiate between hydrocarbons, pentane, C5H12 and pentene, C5H10.
[Molar mass : C5H12 = 72 g mol-1, C5H10= 70 g mol-1]
Reaction
Burnt in air
Observation
Pentane
Burns in yellow flame
with soot.
Pentene
Burns in yellow flame
with more soot.
Table 3(a)
Explain why there is a difference in the observation.
[4m]
(b) Alcohols are non-hydrocarbon compound. Alcohols are widely used as fuel in
daily life. Table 3(b) shows the heat of combustion of various alcohols.
Number of carbon
Molecular formula
Heat of combustion
(kJ mol-1)
atoms
1
CH3OH
-728
2
C2H5OH
-1376
3
C3H7OH
-2016
4
C4H9OH
-2678
Table 3(b)
(i) What is meant by the ‘heat of combustion’?
[2m]
(ii) Write the thermochemical equation for the combustion of propanol.
Then, calculate the volume of carbon dioxide that is released at room
conditions when 1.2 g of propanol is burned in excess oxygen in the
laboratory.
[Relative atomic mass: H,1; C,12; O,16; Molar volume of gas = 24dm3 mol-1
at room conditions]
[4m]
(iii) Based on the information in Table 3(b),
Describe procedures of an experiment in the laboratory to determine the heat of
combustion of one named alcohol. In your answer, include the diagram of the
apparatus set-up and materials used.
[10m]
10. (a) Experiment I and experiment II are carried out to investigate the factors affecting
the discharge of ions at the electrodes.
10
Table 4 shows the apparatus set-up and the observations for the experiment I and
experiment II.
Experiment
Apparatus set-up
Observations
A colourless gas is produced
Cathode
and gives a ‘pop’ sound when
tested with lighted splinter.
A colourless gas is produced
I
and lit a glowing splinter.
Anode
A colourless gas is produced
Cathode
and gives a ‘pop’ sound when
tested with lighted splinter.
The colourless solution around
II
the electrode turns yellow. The
Anode
solution turns blue when tested
with starch solution.
Table 4
Name the products formed at the anodes and cathodes in experiment I and
experiment II. Explain your answer using half-equations. [10m]
(b) Three colourless aqueous solutions in separate reagent bottles have had their
labels removed. You are told that the three solutions are sulphuric acid, sodium
chloride solution and potassium nitrate solution.
Describe the chemical tests to identify each aqueous solution without using any
indicators. Include ionic equations in your answer.
Prepared by:
Checked by:
[10m]
Approved by:
YS (Aug/2013)
11