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Which of the following is suitable for determining different isotopes present in an element which exhibits isotopy?
ASensitive weighing balance
BCathoda ray tube
CMass spectrometer
DGeiger muller counter
EEudiometer
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Question 2
waec1991
Hydrogen is used for the following except
Amanufacturing of ammonia
Bsynthesis of hydrochloric acid
Cextinguishing fire
Dconversion of coal to petrol
Emanufacture of margarine
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Question 3
waec1991
In solution, aminoethanoic acid (glycine) can be represented as NH+3 CH2COO. This implies that it
Ais soluble in all inorganic liquids
Bcan function as a weak acid or a weak base
Cdoes not form salt with mineral acids
Dis highly acidic
Ecannot form esters with alkanols
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Question 4
waec1991
river contaminated by alkali waste will have a pH of about.
A1
B3
C5
D7
E9
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Question 5
waec1991
An organic compound which reacts readily with bromine to form a compound with the formula CH3CHBrCH2Br is
Aethene
Bpropane
Cbutane
Dpropene
Epropyne
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Question 6
waec1991
When a crystal was added to its solution, it did not dissolve and the solution remained unchanged, showing that the solution was
Aconcentrated
Bsupersaturated
Cunsaturated
Dcolloidal
Esaturated
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Question 7
waec1991
A current of 4.0 amperes was passed through copper (ll) tetraoxosulphate (IV) solution for one hour using copper electrodes. What was the mass of copper deposited? (Cu = 64, 1F = 96500 C)
A3.2g
B4.8g
C6.4g
D48g
E96g
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Question 8
waec1991
In which of the following crystals are the particles held by van der Waal's forces only?
ASodium chloride
BIce
CDiamond
DIodine
EQuartz
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Question 9
waec1991
Compounds that have the same molecular formula but different structures are said to be
Aallotropic
Bpolymorphic
Cpolymeric
Disomeric
Eisotopic
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Question 10
waec1991
Which of the following properties is not characteristic of electrovalent compounds?
Aformation of crystalline solids
Bsolubility in polar solvents
Chigh vapour pressures
Dhigh melting and boiling points
Eability to conduct electricity in aqueous solution
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Question 11
waec1991
How many principal electronic shells has an atom whose electronic configuration is shown below? 1s22s22p63s1
A1
B2
C3
D4
E11
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Question 12
waec1991
Which of the following is not a direct petroleum product?
AMethane
BEthanol
CPetrol
DVaseline
EKerosene
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Question 13
waec1991
Which of the reactions represented by the following equations will take place at room temperature?
AC 6 H2O → CO + H2
BCuO + H2 → Cu + H2O
CN2 + 3H2 → 2NH3
D2Na + 2H2O → 2NaOH + H2
E2Fe + 3CI2 → 2FeCI3
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Question 14
waec1991
When starch undergoes complete enzyme-catalyzed hydrolysis, the resulting product is
Aglucose
Bmaltose
Csucrose
Dfructose
Ecellulose
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Question 15
waec1991
In the redox reaction represented by the following equation: Cu2+aq + Zn(s) → Cu(s) + Zn2+
Athe oxidation number of copper increases
Bcopper (ll) ions are reduced to copper atoms
Czinc atoms are reduced to zinc ions
Dcopper (ll) ions donate electrons to zinc atoms
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Question 16
waec1991
The ratio of reactants to products is 1: 3: 2 in the reaction represented by the equation below: N2,/SUB> (g) → 2NH3(g) which of the following law is demonstrated by this?
ABoyle's law
BLaw of multiple proportion
CGay Lussac's law
DLaw of constant composition
EAvogadro's law
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Question 17
waec1991
Esterification of propane 1,2,3-triol and unsaturated higher carboxylic acids will produce
Afats
Bsoap
Cmethly-propanoate
Dalkanols
Eoils
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Question 18
waec1991
2NaNO3 → 2NaNO2 + O2. From the equation above, what is the volume of oxygen produced at s.t.p. when 8.5g of 2NaNO3 is heated until no further gas is evolved? (2NaNO3 = 85, molar volume of gases at s.t.p. = 22.4dm3)
A1.12dm3
B2.24dm3
C4.48dm3
D11.2dm3
E22.4dm3
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Question 19
waec1991
Consider the reaction represented by the equation below: H2(g) + 12(s) ⇌ 2HI(g) ∆H negative. Which of the following takes place when the temperature of the reaction vessel is decreased?
Athe gases condense
Bthe yield of hydrogen increases
Cthe concentration of the reactants remain constant
Dmore of the hydrogen iodide decomposes
Ethe yield of hydrogen iodide increases
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Question 20
waec1991
CH4(g) + 2O2(g) → 2H2O(l) + CO2(g) ∆H = 890KJ mo-1 ∆H in the reaction represented by the equation above is the enthalpy of
