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A compound which liberates carbon (IV) oxide from a hydrogentrioxocarbonate (lV) could have the molecular formula
AC2H5OH
BC 3H 4
CHCOOH
DH2O2
EC6H6
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Question 12
waec1991
In which of the following are the substances arranged in their correct order of increasing melting point?
ASodium chloride, sulphur, diamond
BDiamond, sodium chloride, sulphur
CSulphur, sodium chloride, diamond
DDiamond, sulphur, sodium chloride
ESulphur, diamond, sodium chloride
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Question 13
waec1991
Which of the following statements is not correct? Group 7 elements
Aare diatomic
Bare good oxidizing agents
Care highly electronegative
Dhave relatively low ionization potentials
Ehave high electron affinity
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Question 14
waec1991
Which of the following modes of motion is exhibited by the particles of a solid?
AVibrational and random motion
BVibrational and translational motion
CTranslational and random motion
DVibrational motion only
ETranslational motion only
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Question 15
waec1991
The products of the electrolysis of dilute sodium chlorid solution with platinum electrodes are
Ahydrogen and oxygen
Boxygen and chlorine
Cchlorine and water
Dsodium amalgam and chlorine
Esodium hydroxide and water
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Question 16
waec1991
Which of the following formula is that of a dicarboxylic acid?
A(CH3CH 2)2CHCOOH
BCH2(OH)2
CCH3CH(OH)COOH
DCH2(COOH)2
ECH3COCOOH
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Question 17
waec1991
Brass is an alloy of copper and
Airon
Bchromium
Czinc
Dtin
Emagnesium
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Question 18
waec1991
CH2 = CH2 + H2SO4 → CH3 - CH2 -OSO3H. The reaction illustrated by the equation above is an example of
Asubstitution
Boxidation
Creduction
Daddition
Edisplacement
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Question 19
waec1991
Which of the following elements can from more than one acidic oxide?
AHydrogen
BSulphur
CCarbon
DAlumium
EIron
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Question 20
waec1991
Which of the processes represented by the following equations has the greatest positive entropy change?
AC6H3(l) → C6H 6(g)
BH2O (s) → H2O(l)
CCuO(s) + H2(g) → Cu(s) + H2
DNa2CO3(s) + nH2O(l) →Na 2CO3nH2O(s)
ES(s) → S(l)
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Question 21
waec1991
What is the amount (in mole) of sodium trioxocarbonate (IV) in 5.3 g of the compound? (Na2CO3 = 106)
A0.05
B0.10
C0.20
D0.50
E2.00
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Question 22
waec1991
When air is passed through a heated tube containing finely divided copper, the component that is absorbed in the process is
Acarbon (IV) oxide
Bnitrogen
Coxygen
Dwater vapour
Enoble gases
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Question 23
waec1991
The separation of a mixture of calcium trioxocarbonate (lV) and sodium trioxocarbonate (IV) is most easily carried out by using the differences in their
Aphysical states
Bmelting points
CRf. values
Dsolubility
Eboiling points
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Question 24
waec1991
In which of the following is the oxidation number of nitrogen zero?
ASO2 and NH3
BNaNO3
CHNO2
DNOI3
EN2
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Question 25
waec1991
The metal extracted from cassiterite is
Acalcium
Bcopper
Ctin
Dsodium
Elead
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Question 26
jamb1991
The appropriate test paper to use in the above experiment is moist
Alitmus psper
Bpotassium heptaoxodichromate (IV) paper
Clead (ll) trioxonitrate (V) paper
Duniversal indicator paper
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Question 27
jamb1991
The data in the table above shows the rate of reaction of nitrogen (ll) oxide with chlorine at 25oC It can be concluded that doubling the initial concentration of NO increase the rate of reaction by a factor of
Atwo
Bthree
Cfour
Dfive
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Question 28
jamb1991
50 cm3 of sulphur (lV) oxide, 800 cm3 of carbon (IV) oxide will respectively saturate 1.0cm3 of water at 15oC. Which of the following is suitable for demonstrating the fountain experiment?
ASulphur (IV) oxide and hydrogen chloride.
BCarbon (IV) oxide and ammonia
CAmmonia and hydrogen chloride
DCarbon (IV) oxide and Sulphur (IV) oxide
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Question 29
jamb1991
The electrons of two atoms Y and Z are arranged in shells as shown above. The bond formed between the atoms of Y and Z is
