standardized 3 f4, 2012 with answers
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TRANSCRIPT
NAME: ………………………………………………………………………………..
CLASS: …………………………………………………
TEACHER’S NAME: ………………………………...
MARA JUNIOR SCIENCE COLLEGE
Standardized Test 3 ,2012
CHEMISTRY FORM 4
One and a half hours
INFORMATION FOR CANDIDATES
1. This paper consist of three sections A,B and C.
2. Answer all questions.
This question paper consists of ( 10 )printed pages
PART A ( OBJECTIVES)
1
4541CHEMISTRYJULY20121 ½ hour
4541/1 © 2012 Hak Cipta MRSMPC
Part Question Full mark
Marks
A 10 10
B 1 10
2 10
3 10
C 4 20
Total ( 60)
CONFIDENTIAL
PART A1. The following statements describe the characteristics of an element.
Which of the following shows the group of this element in the Periodic Table?
A. Alkali metalB. Alkali earth metalC. Halogen groupD. 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 increasesC. The numbers of valence electrons increasesD. The number of shells filled with electrons increases
3.Atom Electron configuration
X 2.8.2Y 2.8.7
Table 1Table 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
2
.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
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. HardII. Brittle
III. High melting pointIV. Good electrical insulator
A. I and IV onlyB. II and III onlyC. I, II and IV onlyD. I, II, III and IV only
3
7. The following chemical equation shows the reaction of the Haber processN2 + 3H2 2NH3
Which of the following represent the catalyst, pressure and temperature for this Process ?
Catalyst Temperature , 0C Pressure, atmA Platinum 900 5B Platinum 450 1C Iron 900 450D Iron 450 300
8. Glass X has high density and high refractive index. Glass X can be
A. Fused glassB. Lead crystal glassC. Soda lime glassD. Borosilicate glass
9. Which of the following are the properties of glass?I. Transparent
II. PorousIII. Hard and brittleIV. Good heat and electrical conductors
A. I and IIB. I and IIIC. II and IIID. II and IV
10. Which of the following is correct about the uses of ammonia ?A. manufacture of sulphuric acid and detergentB. manufacture of fertilizer and nitric acidC. as an electrolyte in car batteryD. 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
4
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 ONa 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)
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
5
………………………………………………………………………………………………………………..………………( 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)
…………………………………………………..………………………………………………………( 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.
...…………………….………………………………………………………………………6
[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 : ………………………………………………………………… 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
7
___________________________________________________________________________ [1 mark]
b) State ion discharged at electrode X. Explain why
___________________________________________________________________________
----------------------------------------------------------------------------------------------------------------------- [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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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.
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]
9
Atom X
(c) Sulphuric acid is a very important starting material to manufacture many other useful products. Below is a flow chart for the Contact Process.
(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 B2 D 4 A 6 D 8 B 10 B
STRUCTURE
No scheme mark
1 a Group 18 period 3 1
b High melting point and boiling point/ form coloured compounds or ions/ has more than one oxidation number/can be used as catalysts
1
c Ar, Cl , NaArgon atom has the most protons followed by chlorine and sodium atoms
11
10
Sulphur
Dry air ubstance B
Furnace
Catalyst chamber containing catalyst A at a certain temperature
Dissolve in concentrated sulphuric acid to form substance B
Diluted with substance C
Sulphuric acid
STAGE 1STAGE 2 STAGE 3
increase in proton number will increase the nuclei attraction 1d Correct no. of atoms , labeled nucleus
Correct no of shells of each atom, correct charges for each ion 11
ei low melting point and boiling point/ cannot conduct electricity/ not soluble in water but soluble in organic solvent/ gas at room temperature/ any correct property
1
eii
Correct no. of atoms , labeled nucleus Correct no of shells of each atom , outer shells must overlapp
11
10
2 a Anode ( electrode connected to positive terminal)Cathode ( electrode connected to negative terminal of cell)
1
b Electrical energy to chemical energy 1
c Anode : bromide ionCathode : lead ion
11
d Anode : 2Br- Br2 + 2eCathode : Pb2+ + 2 e Pb
11
e Anode : Brown gas releasedCathode : Grey and shiny solid deposited
11
f Anode: bromine gasCathode: lead metal
1110
3 a Na+ , H+ , Cl- , OH- 1
b Hydrogen ionLower position than sodium ion in electrochemical series
11
c 2H+ + 2e H2 1
d Gas X : hydrogen gasGas Y : chlorine gas
11
e X : position of ions in electrochemical seriesY : concentration of ions in solution
11
f Put the damp blue litmus paper into test tube, It change to red and then decolourized
1110
11
Essay
No Scheme Mark
4a i A : pure metalB : Alloy
11
ii B more suitable than A because B harder than AThe presence of foreign atom with different size destroyed the orderly arrangement of atom in pure metalWhen force is applied, layer of atom in B will not easily slip or slide
1111
iii To improve the appearances/ to prevent rusting / to make the material stronger
1 + 1
b i A long chain molecule made up of smaller molecules called monomer
1
ii Lighter/ durable / easy to mold/ do not rust 1
iii Non-biodegradable – need landfill spacePlastics burning produce toxic gases-harmful to our healthOR plastics may choke rivers or canals
11
c i A: vanadium (v) oxideB: OleumC: water
111
ii 450-5500C 1iii 2SO2 + O2 2SO3 1iv Manufacture of paints/ manufacture of polymer/ production of
fertilizer/ manufacture of detergent/ as electrolyte in car batteries
1 + 1
v Coughing/ chest pain/ shortness of breath/ bronchitis/ lung diseases
1
10
12