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During the electrolysis of dilute tetraoxosulphate (VI) acid solution 0.05 mole of electrons were passed what volume of gas was produced at the anode? (Gaseous molar volume = 22. 4dm3 at s.t.p)
A0.224 dm3
B0.280 dm3
C0.560 dm3
D2.24 dm3
E22.4 dm3
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Question 2
waec1988
The reaction represented by the equation C(s) + H2O(l) → CO(s) + H 2(s) was carried out at 27oC if the enthalpy change was + 4500 J and the entropy change was + 12J, what was the free energy change? (∆G = ∆H - T∆S)
A- 4176 J
B+4176 J
C- 900 J
D+ 900 J
E+8100 J
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Question 3
waec1988
The complex salt formed when aluminium dissolves in sodium hydroxide solution is
ANa3AI(OH)4
BNa2AI(OH)3
CNaAI(OH)3
DNa4AI(OH)4
ENaAI(OH)4
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Question 4
waec1988
When copper (ll) chloride solution is treated with excess aqueous ammonia, a deep blue solution results This is due to the presence of
A(CuNH4)3+ ions
B(CuCI4)2-ions
C[Cu(OH)4]2- ions
DCu(H2-O)42+ IONS
E[cU(NH3)4] ions
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Question 5
waec1988
Which of the following is a waste product in the Solvary Process for the manufacture of sodium trioxocarbonate (IV)?
AAmmonium chloride
BBrine
CLimestone
DCalcium oxide
ECalcium chloride
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Question 6
waec1988
Which of the following correctly explains why iodine crystals change directly into the gaseous state when heated?
Alodine crystals sublime
Blodine atoms are held together by strong forces
Clodine molecules are held together by weak forces
Dlodine molecules are covalent
Elodine is a solid at room temperature
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Question 7
waec1988
Aqueous sodium trioxocarbonate (IV) solution is alkaline because
Aacid from which it is formed is strong
Bsodium is an alkali metal
Csodium trioxocarbonate (IV) is decomposed by water
Dsodium trioxocarbonate (lV) is stable to heat
Esodium triocarbonate (IV) is hydrolysed in water
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Question 8
waec1988
Which of the following equations represents the reaction of chlorine with hot concentrated sodium hydroxide solution?
A2NaOH+CI2 → NaCIO + NaCI + H2O
B4NaOH + 2CI → 4NaCI + 2H2O + O2
C6NaOH + 3CI2 → NaCIO3 + 5NaCI + 3H2O
D2NaOH + CI2 → 2NaCI + H2O2
ENaOH + 2CI2 + H2O → NaCI + 3HCI + O2
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Question 9
waec1988
Which of the following is not a naturally occurring iron ore?
AFeCl2
BFe3O4
CFe2O3
DFeCO3
EFeS2
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Question 10
waec1988
Which of the following metals cannot extracted from its ore by using carbon (ll) oxide as the reducing agent?
ACu
BZn
CAl
DPb
EFe
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Question 11
waec1988
Water gas is a mixture of?
ACO2 and H2
BCO and H2O
CCO2 and CO
DCO and N2
ECO and H2
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Question 12
waec1988
How many isomers can be obtained from C4H10?
Ao
B1
C2
D3
E4
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Question 13
waec1988
What volume of oxygen will be left unreacted when a mixture of 100cm3 of hydrogen and 200cm,sup>3,/sup> of oxygen are exploded in a eudiometer?
A300cm3
B200cm3
C150cm3
D100cm3
E50cm3
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Question 14
waec1988
Which of the following is not true of the rusting of iron?
ARusting is a reduction process
BRusting of iron takes place in the presence of oxygen and moisture
Cthe rust formed is reddish brown
Dthe major constituent of rust is hydrated iron (lll) oxide
Erusting is similar to burning
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Question 15
waec1988
Which of the following is not true of the rusting of iron?
ARusting is a reduction process
BRusting of iron takes place in the presence of oxygen and moisture
Cthe rust formed is reddish brown
Dthe major constituent of rust is hydrated iron (lll) oxide
Erusting is similar to burning
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Question 16
waec1988
Which of the following is not decomposed by heat?
ACaCO3
BCuCO3
CZnCO,sub>3
DNa2CO3
EMgCO3
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Question 17
waec1988
Bubbling of carbon (IV)oxide into calcium hydroxide solution results in the formation of
ACaCO3
BCuCO3
CZnCO3
DNa2CO3
EMgCO3
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Question 18
waec1988
What quantity of silver is deposited when 96500C of electricity is passed through a solution containing silver ions? (Ag = 108, 1F = 96500C)
A1.08g
B40g
C10,.8g
D21.6g
E108g
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Question 19
waec1988
The following are heavy chemicals except
Atetraoxosulphate (IV) acid
Bcaustic soda
Csodium trioxocarbonate (IV)
Dethene
Edyes
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Question 20
waec1988
The main characteristic feature of transition metals is that they
