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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 2
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 3
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 4
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 5
waec1997
Which of the following Group 1 elements has the highest ionization energy?
A55Cs
B37Rb
C19K
D11Na
E3Li
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Question 6
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 7
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 8
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 9
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 10
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 11
waec1997
Lead and tin are the components of
Asteel
Bbronze
Cbrass
Ddentist amalgam
Esoft solder
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Question 12
waec1997
Which of the following is an ore of aluminium?
AHaematite
BMagnetite
CSiderite
DBauxite
ECassiterite
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Question 13
waec1997
Which of the following metals is not extracted by electrolysis ?
Alron
BSodium
CCalcium
DMagnesium
EAluminium
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Question 14
waec1997
The following oxides react with both acids and bases to form salts except
Azinc oxide
Blead (ll) oxide
Caluminium oxide
Dtin (IV) oxide
Ecarbon (Iv) oxide
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Question 15
waec1997
Which of the following is used as water softener?
ANa2CO3.10H2O
BCuSO4. 5H2O
CMgSO4. 7H2O
DCaCI2.2H2O
ENa2SO4. 10H2O
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Question 16
waec1997
Which of the following when heated strongly in air will leave a metal as residue?
ASodium trioxonitrate (V)
BPotassium trioxonitrate (V)
CSilver trioxonitrate (V)
DLead (ll) trrioxonitrate(V)
EAluminium trioxonitrate (V)
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Question 17
waec1997
When chlorine is added to slaked lime, the product obtained is
Ableaching powder
Bchlorinated water
Chydrochloric acid
Doxochlorate (l) acid
Etrioxochlorate (V) salt
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Question 18
waec1997
Which of the substance lettered P to V in the equation below would be left on the filter paper if the reaction mixture were filtered? P (aq) + Q(aq) → V(s) + R(aq) + T(g)
AP
BQ
CV
DT
ER
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Question 19
waec1997
The use of diamond in abrasives is due ti its
Ahigh melting point
Bdurability
Clustre
Dhardness
Eoctahedral shape
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Question 20
waec1997
Which of the following is used widely in the manufacture of flavours and perfumes?
