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A catalyst increases the rate of chemical reaction by
Adecreasing the temperature of the reaction
Bdecreasing the activation energy of the reaction
Cincreasing the surface area of the reactants
Ddecreasing the surface area of the products
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Question 12
waec2009
Which of the following statement is correct? The solubility of
Agases increases with increase in temperature
Bgases decreases with increase in temperature
Cmost solid solutes decreases with indease in temperature
Dmost solid solutes is constant
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Question 13
waec2009
Which of the following salts is insoluble in water?
APb (NO3)2
BNa 2CO3
CAgNO3
DAgCI.
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Question 14
waec2009
A solution that contains as much solute as it can dissolve at a given temperature is said to be
Aconcentrated
Bsaturated
Csupersaturated
Dunsaturated
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Question 15
waec2009
Which of the following acids from normal salt only?
ATetraoxosulphate (IV) acid
BTetraoxophosphate (V) acid
CTrioxonitrate (V) acid
DTrioxosulphate (IV) acid
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Question 16
waec2009
Which of the following hydroxides will readily dissolved in water?
ACu(OH)2
BNaOH
CPb(OH)2
DZn(OH)2
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Question 17
waec2009
Which of the following compounds is not a double salt?
AZn(OH)NO3
BKAI(SO4)2
CKCr(SO4)2
D(NH4)2Fe(SO4)2
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Question 18
waec2009
Which of the following dilute acids does not react with metals to liberate hydrogen?
ACH3COOH(aq)
BHCI(aq)
CH2SO4(aq)
DHNO3(aq)
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Question 19
waec2009
Salts that contain water of crystallization are said to be
Aanhydrous
Bdeliquescent
Cefflorescent
Dhydrated
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Question 20
waec2009
Consider the reaction represented by the following equation: H 2(g) + \(\frac{1}{2}\) O(g) → H 2O(g) ∆H =-285.8 KJmo -1 ∆H represents the enthalpy of
Aformation
Bhydration
Cneutralization
Dsolution
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Question 21
waec2009
In a chemical reaction, ∆H is positive when
AH (product) >H (reactant)
BH(product) < H (reactant)
CH (product) = H (reactant)
DH (product) = Zero (reactant)
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Question 22
waec2009
In a mixture of gases which do not react chemically together, the pressure exerted by the individual gases is called
Aatmospheric pressure
Bpartial pressure
Ctotal pressure
Dvapour pressure
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Question 23
waec2009
Which of the following expressions correctly represents Charles' law?
APV = K
BR \(\alpha \frac{1}{\sqrt{p}\)
CPV = RT
DV = KT
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Question 24
waec2009
What is the value of -14oC on the Kelvin temperature scale?
A259K
B287 K
C287oK
D259oK
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Question 25
waec2009
What is the percentage by weight of calcium in Ca(OCI)2? [Ca = 40, Cl = 35.5, O = 16]
A28.0%
B31.6%
C43.8%
D44.5%
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Question 26
waec2009
Consider the reaction represented by the equation: 2NaHCO3 → Na2CO 3 + H 2O + CO 2. What is the mass of sodium trioxocarbonate (lV) produced by the complete decomposition of 33.6 g of sodium hydrogen trioxocarbonate (IV)? [NaHCO3 = 84, Na2CO3 = 106]
A10.6 g
B16.8 g
C21.2 g
D42.4 g
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Question 27
waec2009
How many molecules are there in 14 g of nitrogen at s.t.p.? [N = 14, Avogadro's c x 10\(^{23}\) mol-1]
A6.02 x 1023
B3.01 x 1023
C8.43 x 1024
D1.20 x 1024
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Question 28
waec2009
The number of particles in one mole of a chemical compound is the
Aatomic number
Bavogadro's number
Cmass number
Doxidation number
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Question 29
waec2009
Which of the following molecules is not linear in shape?
ACO2
BO 2
CNH3
DHCI
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Question 30
waec2009
In bonded atoms, increase in electronegativity difference,
