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Which of the following equations represents a substitution reaction?
AC 2H10(g) + CI 2(g) → C4H9 CI(g) + HCI(g)
BC 2H4(g) + HCI (g) → C 2H5 CI(l)
CC2H2(g) + 2H 2(g) → C 2H6(g)
DC 3H4(g) + 402(g) → 3CO2(g) + 2H 2O(g)
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Question 2
waec2006
The ammonium compound used in the manufacture of dry cells is
ANH4NO3
B(NH4)SO4
CNH4Cl
D(NH4)2CO3
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Question 3
waec2006
Which of the following substance is an ore of iron?
ABauxite
BCassiterite
CHaematite
DSteel
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Question 4
waec2006
Waste plastics accumulate in the soil and pollute the environment because plastic materials are
Ainsoluble in water
Bnon -biodegradable
Ceasily affected by heat
Dinflammab,le
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Question 5
waec2006
Greenhouse effect can be reduced by controlling
Awater evaporation
Bburning wood and fossil fuel
Cthe use of aerosols
Dthe use of artificial fertilizers
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Question 6
waec2006
What is CaHb in the following equation? C a
H b + 5O2 → 3CO 2 + 4H2O
AC 3H4
BC3H6
CC3H8
DC 5H 10
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Question 7
waec2006
Which of the following compounds is an alkanoate?
ACH3COOH
BCH3COOCH3
CCH3CH2OH
DCH3CH2COOH
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Question 8
waec2006
What type of reaction occurs between vegetable oil and plant ash extract?
ADisplacement
BDehydration
CNeutralization
DSaponiflication
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Question 9
waec2006
Which of the following industrial processes is chlorines not used?
AProduction of polyvinylchloride (PVC)
BManufacturing of hydrochloric acid
CManufacturing of common salt
DManufacturing of domestic bleach
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Question 10
waec2006
In the reaction represented by the equation. 5Fe 2+(aq) + MnO-4(aq) + 8H+(aq) → 5Fe3+(aq) + Mn2+(aq) + 4H2O(l) which species is reduced?
AFe2+
BMnO-4
CH+
DFe3+
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Question 11
waec2006
Consider the reaction: 2AI(s) + 6H+(aq) → 2AI3+(aq) + 3H2(g). What is the total number of moles of electrons transferred from the aluminium atoms to the hydrogen ions?
A3
B4
C5
D6
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Question 12
waec2006
Metals can be extracted from their ores by a process involving
Areduction
Boxidation
Chydrolysis
Ddecomposition
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Question 13
waec2006
The oxidation number of iodine in the iodate ion (IO -3) is
A-5
B-1
C+1
D+5
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Question 14
waec2006
Electrolysis is applied in the following processes except
Aelectroplating
Bextraction of aluminium
Cextraction of iron
Dpurification of copper
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Question 15
waec2006
Consider the reaction represented by the equation: 2SO\(_{2(g)}\) + O\(_{2(g)}\) ⇌ 2SO\(_{3(g)}\); ∆H = - 197 kJmol\(^{-1}\). Which of the following conditions will not increase the yield of sulphur (VI) oxide?
AIncrease in temperature
BDecrease in temperature
CIncrease in pressure
DAddition of O2 into the mixture
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Question 16
waec2006
Which of the following compounds absorbs moisture from the atmosphere and dissolves in it?
AFeCI3
BMgSO4.7H2O
CNa2SO 4
DKCI
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Question 17
waec2006
When aqueous ammonia is added to one of the following solutions,a white precipitate which dissolved in excess ammonia is formed Identify the solution.
AZnCl2(aq)
BPb(NO3)2(aq)
CCuSO4(aq)
DFeSO4(aq)
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Question 18
waec2006
The indicator used in neutralizing CH3COOH and NaOH solution has pH range of
A3-5
B7-8
C8-103
D10-12
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Question 19
waec2006
Which of the following aqueous methods cannot be used to distinguish between a strong acid and a a weak acid?
AConductivity measurement
BMeasurement of pH
CMeasurement of heat of neutralization
DAction on starch iodide paper
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Question 20
waec2006
Which of the following processes is an endothermic reaction?