WASSCE CHEMISTRY MAY/JUNE 2011 (SSCE WAEC MAY/JUNE 2011 CHEMISTRY)
1. How many isotopes has hydrogen?
A. 2
B. 3
C. 4
D.5
2. Which of the following electrons configuration correctly represents an inert element?
A. 1s2 2s2 2p4
B. 1s2 2s2 2p6 3s2
C. 1s2, 2s2, 2p6, 3p4
D. 1s2, 2s2, 2p6
3. What type of reaction is represented by the following equation?
$_{1}^{2}D+_{1}^{3}H\to _{2}^{4}He+_{0}^{1}n+energy$
A. Nuclear fission
B. Nuclear fusion
C. Radioactive decay
D. Spontaneous decay
4. Which of the following ions has the electron configuration 2,8,8
A. Na+
B. Mg2+
C.F–
D. Cl–
5. An element with the electron configuration 1s2, 2s2, 2p6 would have a combining power of
A. 0
B. 2
C. 6
D. 8
6. Rare gases are stable because they
A. contain equal number of protons and neutrons
B. contains more electrons than protons
C. are chemically active
D. have octet structure
7. Which of the following element would produce coloured ions in aqueous solution?
A. Calcium
B. Iron
C. Magnesium
D. Sodium
8. The energy change accompanies the addition of an electron to an isolated gaseous atom is
A. bond energy
B. electronegativity
C. electron affinity
D. ionization
9. Which of the following hydrohalic acids is the weakest?
A. HBr
B. HCl
C. HF
D. HI
10. Which of the following arrangement is in order of increasing metallic property?
A. $Li<Na<K$
B. $Na<Li<K$
C. $K<Na<Li$
D. $K<Li<Na$
11. Chlorine, bromine and iodine belong to the same group and
A. are gaseous at room temperature
B. form white precipitate with AgNO3(aq)
C. react violently with hydrogen without heating
D. react with alkali
12.Which of the following elements can conveniently can be placed in two groups in the periodic table
A. Carbon
B. Copper
C. Hydrogen
D. Oxygen
13. The bond formed when two electrons that are shared between two atoms are donated by one of the atoms is
A. covalent
B. dative
C. ionic
D. metallic
14. When element 20A combines with 8Y
A. a covalent compound AY is formed
B .an ionic compound AY is formed
C. an ionic compound A2Y is formed
D. a covalent compound AY2 is formed
15. In metallic solids, the forces of attraction are between the mobile valence electrons and
A. atoms
B. neutrons
C. the negative ions
D. positively charged nuclei
16. Which of the following statement about displacement reaction is correct?
A. more electropositive element displaces a less electropositive one
B. A less electropositive element displaces a more electropositive one
C. The position of elements in the reactivity series has no effect on the reaction.
D. It only occurs when the reaction is at equilibrium
17. The volume occupied by 17g of H2S at s.t.p is [ H= 1.00, S =32.0< Molar Volume =22.4dm3]
A. 11.2dm3
B. 17.0dm3
C.34.0dm3
D. 44.9dm3
18. Consider the reaction represented by the following equation:
$xKMn{{O}_{4(aq)}}+yS{{O}_{2(aq)}}+z{{H}_{2}}{{O}_{(l)}}\to {{K}_{2}}S{{O}_{4(aq)}}+2MnS{{O}_{4(aq)}}+2{{H}_{2}}S{{O}_{4(aq)}}$
X, y and z are respectively
A. 2, 5 and 2
B. 2, 2 and 5
C. 5, 1 and 2
D. 1,5 and 2
19. What is the amount of magnesium that would contain 1.20×1024 particles?
[Mg =24, Avogadro’s constant =6.02×1023]
A. 0.5moles
B. 2.0moles
C. 12.0 moles
D. 24.0moles
20.The number of atoms in one mole of a substance is equal to the
A. mass number
B. oxidation
C. atomic number
D. Avogadro number
21. Which of the following statement about a molar solution is correct?
A. is a supersaturated solution
B. cannot dissolve more of the solute at that temperature
C. contains any amount of solute in a given volume of solution
D. contains one mole of the solute in 1dm3of solution
22. A gas is collected by upward delivery is likely to be
A. heavier than air
B. insoluble in water
C. lighter than air
D. soluble
23. Bubbling excess carbon(IV)oxide into calcium hydroxide solution results in the formation of A. CaCO3
B. CaO
C. Ca(HCO3)2
D.H2CO3
24. The equation $P=\frac{K}{V}$ illustrates
A. Boyle’s law
B. Charles law
C. Dalton law
D. Gay Lussac’s law
25. The initial volume of a gas at 300K was 220cm3. Determine the temperature if the volume became 250cm3.
A. 183K
B. 264K
C. 300K
D. 341K
26. Consider the following energy profile
27.Which of the following equimolar solution has the highest conductivity ?
A. CH3COOH(aq)
B. H2CO3(aq)
C.H2SO4(aq)
D.NaOH(aq)
28. The colour of phenolphthalein indicato in alkaline solution at the end-point of an acid-base titration is
A. colourless
B. Orange
C. pink
D. yellow
29. Which of the following statement about enthalpy of neutralization is correct? It
A. Is constant for a strong acid and a strong base
B. cannot be determined using calorimeter
C. has a positive value
D. is higher fir strong acid and weak base
30. When NH4Cl(aq) was dissolved in water, the container was cold to touch . This implies that
A. the process is endothermic
B. the process is exothermic
C. NH4Cl is highly soluble in water
D.NH4Cl forms a saturated solution
31. Which of the following metallic oxides is amphoteric?
A. Al2O3
B.Fe2O3
C. MgO
D. Na2O
32. On evaporation to dryness, 250cm3of saturated solution of salt X with relative molar mass 101 gave 50.5g of the salt. What is the solubility of the salt
A. 1.0moldm–3
B.20mol dm–3
C. 4.0mol dm–3
D. 5.0mol dm–3
33. Consider the following reaction equation ${{X}_{(g)}}+{{Y}_{(g)}}\rightleftharpoons X{{Y}_{(g)}}\text{ }\Delta H=+220KJmo{{l}^{-1}}$
If the temperature of the system is increased the
A. Backward reaction would be favoured
B. forward reaction would be favoured
C. reaction would stop
D. reaction would be in equilibrium
34. Which of the following condition would lead to an increase in the rate of a reaction?
A. Increase in temperature and decrease in the surface
B. Increase in both temperature and concentration of reactant
C. Decrease in temperature ad increase in concentration of reactants
D. Decrease in temperature and increase in the surface area of reactants
35. What is the value of n in the following equation?
$C{{r}_{2}}O_{7}^{2+}+14{{H}^{+}}+n{{e}^{-}}\to 2C{{r}^{3+}}+7{{H}_{2}}O$
A. 2
B. 3
C. 6
D. 7
36. What mass of copper would be formed when a current of 10.0A is passed through a solution of CuSO4 for 1hour? [Cu = 63.5, 1F = 96500]
A. 5.9g
B.11.8g
C. 23.8g
D. 47.3g
37. Which of the following metals could be used as sacrificial anode for preventing the corrosion of iron?
A. Copper
B. Lead
C. Magnesium
D. Silver
38. Consider the following electrochemical cell notation. ${{M}_{s}}/M_{(aq)}^{2+}\text{ }//H_{(aq)}^{+}/{{H}_{2(g)}}$
The value of the electrode potential is positive when
A. Electrons flow from metal electrode M(s) to hydrogen electrode H2(g)
B. Electrons flow from hydrogen electron H2(g) to metal electrode M(s)
C. the flow of current is high
D. there is equilibrium between the flow of electrons from the hydrogen electrode, H2(g) to metal electrode, M(s)
39. Which of the following compounds determines the octane rating of petrol?
A. 1, 2, 3 – trimethylpentane
B. 2, 3, 5 – trimethyloctane
C.2, 3, 5 – trimethylpentane
D. 2, 2, 4 – trimethylpentane
40.Which of the following compounds would react with ethanoic acid to give a sweet smeeling liquid?
A. Alkane
B. Alkanol
C. Alkanal
D. Alkyne
41. Which of the following separation techniques would show that black ink is a mixture of chemical compounds
A. Crystallization
B. Chromatography
C. Filtration
D. Sublimation
42. The following substance are examples of addition polymer except
A. nylon
B. Perspex
C. polyethane
D. Polychloroethane
43. When bromine is added to ethane at room temperature, the compound formed is
A. 1, 1 – dibromoethane
B. 1, 1 – dibromoethene
C. 1,2 – dibromoethane
D. 1, 2 – dibromoethene
44. Which of the following organic compounds would react with sodim trioxocarboate (IV) to liberate carbon (IV) oxide
45.The compound that makes palm win taste sour after exposure to the air for few days
A. ethanol
B. ethanoic acid
C. methanol
D. methanoic acid
46. The reagent that can be used to distinguish ethane from ethyne is
A. ammoniacal silver tioxonitrate(V) solution
B. Benedict solution
C. Bromine water
D. Fehling solution
47. The following substance are ores or metal except
A. Bauxite
B. Cuprite
C. Cassisterite
D. graphite
48. Which of the following processes does not involve the use of limestone?
A. Extraction of iron in the blast furnace
B. Manufacture of tetraoxoslphate(VI) acid by contact process
C. Production of washing soda by solvay process
D. Production of cement
49.Which of the following substance is mainly responsible for the depletion of ozone layer
A. Chlorofluorocarbon
B. Carbon(IV)oxide
C. Nitrogen
D. Oxygen
50. Aluminium is extracted by electrolysis from
A. bauxite
B. Cryolite
C. Duralumin
D. Kaolin