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The by-product of the fermentation of sugar to ethanol is
Apropane -1,2,3-triol
Bethyl ethanoate
Cethanedioc acid
Dpropanol
Ecarbon (lV) oxide
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Question 13
waec1997
Which of the following is the relative molecular mass of a compound which has empirical formula CH\(_2\)O? (H = 1; C = 12; O = 16)
A42
B45
C126
D180
E145
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Question 14
waec1997
The reaction between alkanoic acids and alkanols in the presence of a mineral acid is known as
Asaponification
Bhydrolysis
Cpolymerization
Desterification
Edehydration
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Question 15
waec1997
Ethene undergoes mainly addition reactions because it is
Aa gas
Ba hydrocarbon
Cunsaturated
Deasily polymerized
Ea covalent compound
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Question 16
waec1997
Separation of mixture of solids by physical methods can be based on differences in the following except
Amelting point
Bsolubility
Cparticle size
Dmolar mass
Emagnetic property
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Question 17
waec1997
The position of equilibrium in a reversible reaction is affected by
Aparticle size of the reactants
Bchange in concentration of the reactants
Cchange in size of the reaction vessel
Dvigorous stirring of the reaction mixture
Epresence of a catalyst
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Question 18
waec1997
How much heat will be liberated if 8g of hydrogen burns in excess oxygen according to the following equation? 2H2 + O2→ 2H2O,∆H = -571.7KJ (H = 1)
A1.42.9KJ
B571.7KJ
C1143.4KJ
D285.9KJ
E2286.8KJ
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Question 19
waec1997
If the value of ∆H for a reaction is negative, it means that the reaction is
Aslow
Bexothermic
Cspontaneous
Dirreversible
Enot feasible
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Question 20
waec1997
What is the value of x in the following equation? MnO- 4 + 4H+ + xe- → MnO 2 + 2H2O
A2
B3
C4
D7
E8
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Question 21
waec1997
From the following equations, what is the order of decreasing reactivity of X, Y and Z? Y (s) + X2+(aq) → Y2+(aq) + X(s) X(s) + Z2+(aq) → X2+(aq) + Z(s)
AX>Y>Z
BY > X > Z
CZ > Y > X
DY > Z > X
EX > Z > Y
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Question 22
waec1997
The common feature of reactions at the anode is that
Aelectrons are consumed
Boxidation is involved
Cions are reduced
Dthe electrode dissolves
Ethe electrolyte is diluted
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Question 23
waec1997
What quantity of electrons (in mole) is lost when one mole of iron (ll) ions is oxidized to iron (lll) ions?
A5 mole
B4 mole
C3 mole
D2 mole
E1 mole
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Question 24
waec1997
Which of the following ions will migrate to the cathode during electrolysis?
AZinc ions
BChloride ions
CSulphide ions
DTetraoxosulphate (Vl) ions
ETrioxonitrate (V) ions
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Question 25
waec1997
The loss of molecules of water of crystallization to the atmosphere by some crystalline salts is known as
Aefflorescence
Beffervescence
Cphosphorescence
Dfluorescence
Edeliquescence
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Question 26
waec1997
Which of the following is a general method of preparing acids?
ADirect combination of constituent elements
BReaction between a base and an amphoteric oxide
CDouble decomposition involving a salt solution
DReaction between an anhydride and water
EDissolution of hydroxides followed by neutralization
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Question 27
waec1997
Which of the following is a general method of preparing acids?
ADirect combination of constituent elements
BDouble decomposition involving a salt solution
CReaction between an anhydride and water
DReaction between a base and an amphoteric oxide
EDissolution of hydroxides followed by neutralization
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Question 28
waec1997
An acid is a substance which in the presence of water produces
Asalts
Boxygen
Ceffervescence
Dhydroxonium ions
Ehydrogen gas
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Question 29
waec1997
A given volume of methane diffuses in 20 seconds. How long will it take the same volume of sulphur (IV) oxide to diffuse under the same conditions? [CH\(_4\) = 16; SO\(_2\) = 64]
A5 seconds
B20 seconds
C40 seconds
D60 seconds
E80 seconds
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Question 30
waec1997
An increase in the pressure of a gas results in a decrease in its
