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What is the role of MnO2 in the reaction represented by the following equation?MnO2 + 4HCI2 + CI2 + 2H2O
ABleaching agent
BOxidizing agent
CAmphoteric oxide
DBasic oxide
ECatalyst
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Question 662
waec1996
The cleansing action of soap in hard water is not satisfactory because soap
Aforms insoluble calcium and magnesium salts
Bis made from fats and oils
Chas an organic component
Dalters the surface tension of water
Eis a sodium salt of higher carboxylic acids
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Question 663
waec1996
During water treatment for town supply, water is passed through layers of send beds in order to
Asoften the water
Bfilter the water
Cdecolorize the water
Ddestroy the germs in the water
Ecoagulate colloidal particles in the water
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Question 664
waec1996
The component of air that can be removed by alkaline pyrogallol solution is
Aoxygen
Bnitrogen
Cwater vapour
Dcarbon (IV) oxide
Enoble gases
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Question 665
waec1996
Use this following information to answer this question. Compound X was boiled with concentrated hydrochloric acid for a long time. One of the products was found to be a sugar. What type of reaction was involved between compound X and concentrated hydrochloric acid?
APolymerization
BFermentation
CHydrolysis
DNeutralization
EEsterification
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Question 666
waec1996
Use this following information to answer this question. Compound X was boiled with concentrated hydrochloric acid for a long time. One of the products was found to be a sugar. Compound X was probably
Arubber
Bpolyethene
Cnylon
Dcellulose
Eethanol
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Question 667
waec1996
Which of the following is a disaccharide?
Afructose
Bstarch
Ccellulose
Dsucrose
Eglycogen
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Question 668
waec1996
When excess carbon (lV) oxide is passed into lime water, the turbidity produced initially disappears due to the formation of
Acalcium oxide
Bcalcium carbide
Ccalcium hydrogentrioxocarbonate (IV)
Dtrioxocarbonate (IV) acid
Ecalcium trioxocarbonate (IV)
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Question 669
waec1996
What amount of hydrogen will be required for complete hydrogenation of one mole of pent-3-yne?
A1 mole
B2 moles
C3 moles
D5 moles
E6 moles
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Question 670
waec1996
When acidified KMnO4 solution is decolorised by ethene, the gas acts as
Aa straight-chain hydrocarbon
Ba saturated hydrocarbon
Ca reducing agent
Da dehydrating agent
Ean oxidizing agent
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Question 671
waec1996
On exposing palm wine to air for some days, it becomes sour owing to the conversion of
Aglucose to ethanol
Bglucose to gluconic acid
Cethanol to ethanoic acid
Dethanol to ethanal
Epalm wine to palmitic acid
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Question 672
waec1996
Which of the following exhibits resonance?
ABenzene
BButane
CPentene
DOctana
EHexene
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Question 673
waec1996
If the third member of a homologous series is C3H8, the fifth member will be
AC 5H8
BC5H9
CC5H10
DC5H11
EC5H12
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Question 674
waec1996
What does X represent in the following equation? H 2(g) + 1/2O2(g) → H2O (l); ∆H = xKJ.
ABond energy
BActivation energy
CIonization energy
DEnthalpy of neutralization
EEnthalpy of formation
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Question 675
waec1996
The rate of production of hydrogen gas from the reaction between zinc granules and hydrochloric acid can be increased by
Acooling the reaction mixture
Busing zinc powder instead of zinc granules
Cusing zinc rod instead of zinc granules
Dcarrying out the reaction at a higher pressure
Ecarrying out the reaction in a closed vessel
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Question 676
waec1996
Which of the following is not correct about a catalyst? It
Aremains unchanged chemically at the end of a reaction
Bhelps to establish equilibrium faster reversible reaction
Ccan start a chemical rection which will normally not take place
Dis usually specific in its action
Ealters the rate of chemical reaction
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Question 677
waec1996
Which of the following statements is not correct about electrolysis?
AReduction occurs at the anode
BAnions migrate to the anode
CPositive ions migrate to the cathode
DConcentration affects the discharge of ions
EElectrolytes conduct electric current
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Question 678
waec1996
In which of the following compounds is the oxidation number of nitrogen equal to + 3?
ANO 2
BN 2O
CNO
DHNO2
EHNO3
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Question 679
waec1996
An arrangement of two different metals in aqueous solutions of their salts to produce an electronic current is known as
