Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.
Which of the following measures is not suitable for controlling water pollution?
Atreating industrial effluent and domestic sewage before discharge into water
BControlling the use of agrochemicals
Crecycling industrial and agricultural wastes
Dburning industrial and agricultural wastes before discharge into water ways
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Question 2
waec2004
The process of seeding during the extraction of aluminium involves the addition of pure AI(OH)3 crystals in order to
Alower the temperature
Bincrease the concentration
Cfacilitate the precipitation of solid
Dreduce the viscosity of the solution
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Question 3
waec2004
Which of the following pollutants is biodegradable?
ADomestic sewage
BMetal scraps
CRadioactive waste
DPlastic foil
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Question 4
waec2004
Which of the following is required in an experiment to determine the enthalpy of solution of anhydrous CuSO? l. Mass of the anhydrous CuSO 4 II. Volume of water in which the CuSO4 is dissolved lll. lnitial temperature of water lV. Final temperature of the solution
Al and ll only
Blll and IV only
Cll, lll, and IV only
Dl, ll, lll, and IV only
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Question 5
waec2004
What is the product Cx Hy in the following equation? \(C_{10}H_{22}\) → \(C_{8}H_{18}\) + CxHy
Abutene
Boctane
Cethene
Ddecane
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Question 6
waec2004
WHICH OF THE FOLLOWING PETROLEUM FRACTIONS YIELDS VASELINE AND PARAFFIN WAX ON REDISTILLATION?
ADIESEL OIL
BLUBRICATION OIL
CPETROL
DKEROSENE
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Question 7
waec2004
Which of the following reactions will be affected by change in pressure at equilibrium?
AX(g) + Y(g) ⇌ W(g) + Z(g)
BX(g) + 2Y(g) ⇌W(g) + Z(g)
C2X(g) ⇌ W(g) + Z(g)
D2Y(g) ⇌ W(g) + Z(g)
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Question 8
waec2004
The key factor to be considered in siting a chemical industry is
Afavourable climatic conditions
Bthe availability of space to store raw materials
Cits nearness to other industrial establishments
Dits nearness to the source of raw materials
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Question 9
waec2004
What is the change in the oxidation number of 1- in the reaction represented by the following equation? 51 -1(aq) + 6H+(aq) + 1O-3(aq) → 312(g) + 3H2O(l)
A-5 to -3
B-1 to 0
C+ 5 to + 0
D-1 to + 2
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Question 10
waec2004
Which of the following statements is true of an endothermic reaction? I. Heat is absorbed from the surrounding II. The heat content of the products is more than that of the reactants III. The enthalpy change is positive IV. The surrounding is at a lower temperature than the system.
Al only
Bl and ll only
Cl,ll and lll only
Dl, ll, lll and lV
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Question 11
waec2004
The condensation of several amino acid molecules gives
Along chain alkanoic acids
Bsecondary alkanols
Calkanoates
Dproteins
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Question 12
waec2004
When ammonium trioxocarbonate (IV) solution is added to separate solutions of calcium, zinc and sodium salt precipitate could be formed in the case of
Acalcium only
Bzinc only
Ccalcium and znic only
Dsodium and zinc only
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Question 13
waec2004
Consider the cell represented below: Zn/Zn2+(aq) // Cu2+(aq) / Cu(s). Which of the following statements is correct about the cell
AZn is oxidized to Zn2+
BCu is oxidized to Cu2+
CIt is an electrolytic cell
Deach single line represents a salt bridge
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Question 14
waec2004
If 60 cm3 of gas is heated from 27oC TO 50oC, what is the new volume of the gas at constant pressure?
A32.4cm 3
B55.7cm3
C64.6cm3
D111.1cm3
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Question 15
waec2004
An orange drink concentrate is suspected to contain traces of poisonous green dye and a harmless dye having the same boiling point. Which of the following techniques is most suitable for isolating the dyes?
AFractional distillation
BPaper chromatography
CCoagulation
DRecrystallization
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Question 16
waec2004
Which of the following factors that affect the rate of chemical reactions can be explained in terms of the collision theory? l. concentration ll. pressure lll. temperature lV catalyst
Al and ll only
Bl, ll and lll only
Cl and lll only
Dl, II, lll and IV only
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Question 17
waec2004
WHICH OF THE FOLLOWING SALTS IS READILY SOLUBLE IN WATER?
APbCI2
BPb(NO 3) 2
CPbSO4
DPbCO 3
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Question 18
waec2004
What of the following pairs of acid and base will produce a solution with pH less than 7 at equivalence point?
AHNO3 and NaOH
BH2SO4 and KOH
CHCI and Mg(OH) 2
DHNO 3 and KOH
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Question 19
waec2004
The reaction that takes place at the cathode when an aqueous solution of NaCI is electrolysed using carbon electrodes is
A2H+2(g) + 2e- → H2(g)
BNa+2(g) + e- → Na(s)
C4OH- → 2H2O(l) + O2(g) +4e-
D2CI- → CI2(g) + 2e-
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Question 20
waec2004
Which of the following compounds is a soapless detergent?
