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What is the function of sulphur (IV) oxide in the reaction represented by the following equation? SO 2(aq) + 2H2S(g) → 3S (s) + 2H 2O (l)
ADehydrating agent
BOxidising agent
CBleaching agent
DAcid
EPrecipitant
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Question 632
waec1998
Which of the following methods is suitable for the preparation of an insoluble salt?
AAction of an acid on a metal
BDouble decomposition
CNeutralisation
DAction of an acid on a trioxocarbonate (IV)
EAction of an acid on an oxide
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Question 633
waec1998
Which of the following is not a property of trioxonitrate (V) salts?
APositive reaction to the brown ring test
BAbility to dissolve in cold water
CDecomposition on being strongly heated
DProduction of effervescence with saturated Na2CO3 solution
EEvolution of gas with concentrated H2SO4 and copper turnings
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Question 634
waec1998
The following oxides react with water except
ANa2O
BSO3
CNO2
DCO2
ECuO
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Question 635
waec1998
AN AQUEOUS SOLUTION IS ACIDIC IF
Aits pH value is high
Bit s corrosive
Cit changes the colour of litmus
Dit has a bitter taste
Eit contains more H3O- than OH-
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Question 636
waec1997
What is the basicity of the acid in the followed reaction? NaCO + 2CHCOOH → 2CH COONa + H2O + CO2
A1
B2
C3
D4
E8
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Question 637
waec1997
A mixture of NaCI(s) and CaCO3(s) is best separated by
Adissolution followed by filtration
Bsublimation followed by crystallization
Cdissolution followed by evaporation
Ddissolution followed by crystallization
Esublimation followed by dissolution
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Question 638
waec1997
What volume of oxygen at s.t.p would react with carbon to form 4.40g of CO2 according to the following equation? C(s) + O2(g) → CO2(g) [O = 16; C =12; 1 mole of a gas occupies 22.4dm3 at s.t.p]
A0.224dm3
B2.24dm3
C4.40dm3
D4.48dm3
E22.4dm3
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Question 639
waec1997
Boyle's law can be expressed mathematically as
AV \(\alpha\) T (P constant)
BP \(\alpha\) V (T constant)
CP \(\alpha\) T
DV \(\alpha\) 1 / p(T constant)
EV1/T1 = / T2
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Question 640
waec1997
Which of the following Group 1 elements has the highest ionization energy?
A55Cs
B37Rb
C19K
D11Na
E3Li
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Question 641
waec1997
Which of the following statements is correct about sodium chloride in the solid state?
Ait exists as aggregates of ions
Bit conducts electricity
Cits melting point is below 100oC
Dit exists as discrete molecules
Eits ions are linked by metallic bonds
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Question 642
waec1997
The valence electrons of element 12Mg are in the
A1s orbital
B2s orbital
C2px orbital
D2py orbital
E3s orbital
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Question 643
waec1997
Element X, with electronic configuration 2, 8, 2 and element Y with electronic configuration 2, 8, 7 are like to combine by
Ametallic bonding
Bcovalent bonding
Celectrovalent bonding
Ddative bonding
Ehydrogen bonding
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Question 644
waec1997
If an element R belongs to the same group as sodium, an aqueous solution of ROH will
Abe neutral
Bbe acidic
Cbe coloured
Dhave pH greater than 7
Eturn back litmus red
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Question 645
waec1997
An atom 17 protons, 17 electrons and 18 neutrons has a mass number of
A17
B18
C34
D35
E52
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Question 646
waec1997
Lead and tin are the components of
Asteel
Bbronze
Cbrass
Ddentist amalgam
Esoft solder
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Question 647
waec1997
Which of the following is an ore of aluminium?
AHaematite
BMagnetite
CSiderite
DBauxite
ECassiterite
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Question 648
waec1997
Which of the following metals is not extracted by electrolysis ?
Alron
BSodium
CCalcium
DMagnesium
EAluminium
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Question 649
waec1997
The following oxides react with both acids and bases to form salts except
