2. PART A
1. The following statements describe the characteristics of an element.
.Aqueous solutions of its ions are green or brown in colour
.Used as catalyst in the Haber Process
.Has two oxidation numbers +2 and +3
Which of the following shows the group of this element in the Periodic Table?
A. Alkali metal
B. Alkali earth metal
C. Halogen group
D. Transition element
2. Which statement explains why the size of the atoms of group 1 elements increases
when
going down the group in the periodic table?
A. The number of protons increases
B. The relative atomic mass increases
C. The numbers of valence electrons increases
D. The number of shells filled with electrons increases
3.
Atom Electron configuration
X 2.8.2
Y 2.8.7
Table 1
Table 1 shows the electron configuration of element X and Y. Which of the
following is true for compound formed from the reaction between X and Y?
Bonding type Electric conductivity
A ionic in aqueous and molten state
B covalent in aqueous and molten state
C covalent in aqueous state only
D ionic in molten state only
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3. 4. The diagram set up apparatus of an experiment .
The ammeter shows a deflection . Which of the following represent substance K ?
I Molten lead (II) bromide
II Potassium Iodide solution
III Pure ethanol
IV Molten naphthalene
A I and II only
B II and IV only
C I,II and III only
D I,II,III and IV only
5. Electrolysis of copper (II) sulphate solution 0.5 mol dm-3 using electrodes copper .
Which of the following equations represent the reaction at anode and cathode. ?
Anode Cathode
A 2Cl- Cl2 +2e 2H+ +2e H2
B Cu Cu2+ + 2e Cu2+ + 2e Cu
C 4OH- 2H2O + O2 + 4e 2H+ +2e H2
D 4OH- 2H2O + O2 + 4e Cu2+ + 2e Cu
6. Which of the following describe the characteristics of ceramics?
I. Hard
II. Brittle
III. High melting point
IV. Good electrical insulator
A. I and IV only
B. II and III only
C. I, II and IV only
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4. D. I, II, III and IV only
7. The following chemical equation shows the reaction of the Haber process
N2 + 3H2 2NH3
Which of the following represent the catalyst, pressure and temperature for this Process ?
Catalyst Temperature , 0C Pressure, atm
A Platinum 900 5
B Platinum 450 1
C Iron 900 450
D Iron 450 300
8. Glass X has high density and high refractive index. Glass X can be
A. Fused glass
B. Lead crystal glass
C. Soda lime glass
D. Borosilicate glass
9. Which of the following are the properties of glass?
I. Transparent
II. Porous
III. Hard and brittle
IV. Good heat and electrical conductors
A. I and II
B. I and III
C. II and III
D. II and IV
10. Which of the following is correct about the uses of ammonia ?
A. manufacture of sulphuric acid and detergent
B. manufacture of fertilizer and nitric acid
C. as an electrolyte in car battery
D. as a pigment in paint
ANSWER COLUMN (please write your answer here, A /B / C/ D )
1 3 5 7 9
2 4 6 8 10
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5. PART B
1) Elements carbon, oxygen, sodium, chlorine , argon and element W are situated in the
periodic table as shown in the periodic table below
C O
Na Cl Ar
W
a) Where is element argon placed in the periodic table?
( state which group and period)
…………………………………………………………………………………………………………………….…………( 1m)
b) W is a transition element. State one special property of W
…………………………………………………………………………………………………………………….…………( 1m)
c) Arrange atoms Na, Cl and Ar according to increasing size of atoms.
Explain reason for your choice.
…………………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………….…………………
……………………………………………………………………………………………………………………….………( 3m)
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6. d) Both sodium atom and oxygen atom are not stable. They react to form an ionic
compound which is more stable.
Draw electron arrangement for compound formed between sodium atom and oxygen
atom
Given proton number of Na, 11; O, 8
………………………………………………………………………………………………………………..………………( 2m)
e) Element C reacts with element Cl to form a covalent compound with a formula CCl4.
i) State one physical properties of this covalent compound ( 2 m)
…………………………………………………..………………………………………………………( 1m)
ii) Draw electron arrangement of the compound CCl4
(Given proton number of C, 6 ; Cl ,17)
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7. …………………………………………………..………………………………………………………( 2m)
2) Figure 2 below shows the apparatus arrangement to study the electrolysis of molten
lead (II) bromide
a) Identify the cathode and the anode on the figure above by writing the word “cathode”
and “anode” in the figure.
[1 mark]
b) State the energy changes that occur in the process.
...…………………….………………………………………………………………………
[1 mark]
c) Which ions attracted to :
(i) Anode : …………………………………………………………………………………
(ii) Cathode : ………………………………………………………………………………
[2 marks]
d) Write the half equation for the reaction occurred
i) At the anode : …………………………………………………………………
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8. ii) At the cathode: …………………………………………………………………
[2 marks]
e) What observations can be made at
(i) Anode?
……………………………………………………………………………………………
[1 mark]
(ii) Cathode?
……………………………………………………………………………………………
[1 mark]
f) Name the substances formed at each of the electrodes
i) Anode :………………………………………………………………………..
ii) Cathode : ……………………………………………………………………
[2 marks ]
3) Diagram below shows the apparatus set-up for the electrolysis of 1.0 mol dm-3
sodium chloride solution using carbon electrodes X and Y .
a) Write the formulae of all ions present in sodium chloride solution
___________________________________________________________________________
[1 mark]
b) State ion discharged at electrode X. Explain why
___________________________________________________________________________
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9. -----------------------------------------------------------------------------------------------------------------------
[2 marks]
c) Write the half-equation for the reaction occurring at electrode X
___________________________________________________________________________
[1 mark]
d) State the product formed at each electrode:
Gas X - _____________________________________
Gas Y - _____________________________________ [2 marks]
e) State the factor that affect the electrolysis at
i) electrode X
_______________________________________________________
[1 mark]
ii) electrode Y
___________________________________________________
[1 mark]
f) How do you test the presence of the gas at electrode Y?
_________________________________________________________________________
________________________________________________________________________
[2
marks]
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10. PART C (Essay )
4. (a) Diagram 4 shows the arrangement of atoms in two types of materials, A and B.
Material B is more suitable than material A to make railway tracks.
Atom X
Material A Material B
Diagram 4
(i) State the types of material A and material B.
[2 m]
(ii) Explain, in terms of arrangement of atoms, why material B is more suitable
to make railway tracks. [4 m]
(iii) Alloy such as bronze, brass and stainless steel are commonly used in
our daily lives. State two aims of making alloys. [2m]
(b) Many everyday items are made of plastic. Plastic is a synthetic polymer.
(i) What are polymers [1m]
(ii) State one advantage of using plastics [1m]
(ii) How do synthetic polymers pose environmental problem?. [2m]
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11. (c) Sulphuric acid is a very important starting material to manufacture many other
useful products. Below is a flow chart for the Contact Process.
Sulphur Catalyst Dissolve in Diluted
chamber concentrated with Sulphuric
Furnace
Dry air containing sulphuric substance acid
catalyst A at a acid to form C
certain substance B
temperature
STAGE 1
STAGE 2 STAGE 3
(i) Identify substances A , B and C [3m]
(ii) What is the range of temperature suitable in STAGE 2 ? [ 1m]
(iii) Write chemical equation for reaction in STAGE 2 [ 1 m]
(iv) Give two uses of Sulphuric acid [2m]
(v) What is the effect if you inhale sulphur dioxide? [ 1m]
Answers - Standardized test 3
Obj
1 D 3 A 5 B 7 D 9 B
2 D 4 A 6 D 8 B 10 B
STRUCTURE
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13. 1 a Group 18 period 3 1
b High melting point and boiling point/ form coloured compounds or ions/ has more 1
than one oxidation number/can be used as catalysts
c Ar, Cl , Na 1
Argon atom has the most protons followed by chlorine and sodium atoms 1
increase in proton number will increase the nuclei attraction 1
d Correct no. of atoms , labeled nucleus 1
Correct no of shells of each atom, correct charges for each ion 1
ei low melting point and boiling point/ cannot conduct electricity/ not soluble in water 1
but soluble in organic solvent/ gas at room temperature/ any correct property
ei Correct no. of atoms , labeled nucleus 1
i Correct no of shells of each atom , outer shells must overlapp 1
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2 a Anode ( electrode connected to positive terminal) 1
Cathode ( electrode connected to negative terminal of cell)
b Electrical energy to chemical energy 1
c Anode : bromide ion 1
Cathode : lead ion 1
d Anode : 2Br- Br2 + 2e 1
Cathode : Pb2+ + 2 e Pb 1
e Anode : Brown gas released 1
Cathode : Grey and shiny solid deposited 1
f Anode: bromine gas 1
Cathode: lead metal 1
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3 a Na+ , H+ , Cl- , OH- 1
b Hydrogen ion 1
Lower position than sodium ion in electrochemical series 1
c 2H+ + 2e H2 1
d Gas X : hydrogen gas 1
Gas Y : chlorine gas 1
e X : position of ions in electrochemical series 1
Y : concentration of ions in solution 1
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14. f Put the damp blue litmus paper into test tube, 1
It change to red and then decolourized 1
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Essay
No Scheme Mark
4a i A : pure metal 1
B : Alloy 1
ii B more suitable than A because B harder than A 1
The presence of foreign atom with different size 1
destroyed the orderly arrangement of atom in pure metal 1
When force is applied, layer of atom in B will not easily slip or 1
slide
iii To improve the appearances/ to prevent rusting / to make the 1+1
material stronger
b i A long chain molecule made up of smaller molecules called 1
monomer
ii Lighter/ durable / easy to mold/ do not rust 1
iii Non-biodegradable – need landfill space 1
Plastics burning produce toxic gases-harmful to our health 1
OR plastics may choke rivers or canals
c i A: vanadium (v) oxide 1
B: Oleum 1
C: water 1
ii 450-5500C 1
iii 2SO2 + O2 2SO3 1
iv Manufacture of paints/ manufacture of polymer/ production of 1+1
fertilizer/ manufacture of detergent/ as electrolyte in car
batteries
v Coughing/ chest pain/ shortness of breath/ bronchitis/ lung 1
diseases
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