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The alloy used for metal work and plumbing contains
Alead and tin
Biron and carbon
Ccopper and tin
Daluminium and copper
Elead and antimony
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Question 2
waec1993
Zinc displaces copper from an aqueous solution of copper (ll) salt because
Acopper is a transition element
Bcopper is a moderately reactive metal
CZinc and copper have reducing prperties
Dzinc is more reactive than copper
Ezinc reacts with both acids and alkalis
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Question 3
waec1993
When ammonium chloride is dissolved in water in a test tube, the tube feels colder showing that
Athe solution is unsaturated
Bsublimation has ocurred
Cammonia gas is evolved
Dthe process is endothermic
Econdensation has occurred
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Question 4
waec1993
The product of the reaction between ethanol and excess acidified K\(_2\)Cr\(_2\)O\(_7\) is
Aethanal
Bethylethanoate
Cethanoic acid
Dethyne
Eethanedioic acid
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Question 5
waec1993
Which of the following is correct about the electrons in the 1s orbital? They
Ahave the same spin
Bare easier to remove than those in the 2p orbital
Care closest to the nucleus
Dhave the same energy as those in the 2s orbital
Ehave different magnetic quantum numbers
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Question 6
waec1993
Which of the following gases are diatomic except
Anitrogen
Bhelium
Chydrogen
Dfluorine
Eoxygen
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Question 7
waec1993
An alkene may be converted to an alkane by
Ahalogenation
Bhydrolysis
Cdehydration
Dhydrogenation
Edecomposition
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Question 8
waec1993
Producer gas is a mixture of
Aoxygen and hydrogen
BHydrogen and nitrogen
Cnitrogen and oxygen
Dnitrogen and carbon (ll) oxide
Ehydrogen and carbon (ll) oxide
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Question 9
waec1993
In which of the following pairs are both substances deliquescent?
ACaCI2 and H2SO4
BNaOH and MgSO4 7H2O
CCaCI2 and NaOH
DCUO and NaCI
ECaCO3 and MgCI2
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Question 10
waec1993
Which of the following compounds of tin is a strong reducing agent?
ASnCI2
BSnCI4
CSnO2
DSnH4
ESn(OH)2
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Question 11
waec1993
When the trioxonitrate (IV) salt of an alkali metal Y is heated, the formula of the residue is
AY2O
BYNO2
CY2O3
DY (NO2)2
EYO2
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Question 12
waec1993
Examples of polymers include the following except
Astarch
Bnylon
Cwool
Dperspex
Eglass
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Question 13
waec1993
Which of the following will not affect the degree of hardness in a sample of temporarily hard water?
AAddition of washing soda
BAdding of soap
CTreatment with carbon exchange resin
DFiltration
EDistillation
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Question 14
waec1993
The component of air that removed when air is bubbled into alkaline pyrogallol solution is
Acarbon(lV) oxide
Boxgyen
Cwater vapour
Dnitrogen
Ehelium
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Question 15
waec1993
Which of the following substances is a peroxide?
ANa2O2
BCuO
CPb
DFe2O
EAI2O
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Question 16
waec1993
Which of the following indicates the correct increasing order of oxidizing power of the halogens?
AF < CI < Br < l
Bl < Br < CI < F
CI < CI < Br < F
DBr < I < CI < F
ECI < F < I < Br
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Question 17
waec1993
What volume of distilled water should be added to 400cm3 of 2.0 mole dm-3 \(H_{2}SO_{4}\) to obtain 0.20 mole dm-3 of solution>
A600cm-3
B800cm-3
C1,000cm-3
D3,600cm-3
E4,000cm-3
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Question 18
waec1993
The following gases decolorize bromine water except
AC2H6
BC2H4
CC2H2
DC3H4
EC3H6
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Question 19
waec1993
Consider the reaction represented by the following equation CaCI2(aq) + H 2C2O 4(aq) ⇌ CaC 2O4(s) + 2HCI(aq). Which of the following would dissolve the precipitate of CaC 2O4 formed?
AStirring the mixture vigorously
BAdding more calcium chloride solution
Clncreasing the concentration of the ethanedioic acid
DAdding concentrated hydrochloric acid
EAdding some distilled water
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Question 20
waec1993
Some precious stones such as ruby and sapphire consist of aluminum oxide coloured by traces of the oxides of
