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A sample of air that has been passed through caustic potash will
Acontain more oxygen than nitrogen
Brekindle a glowing splint
Chave no action on lime water
Dcontain no water vapour
Ebe free of noble gases
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Question 2
waec1985
Chlorine is prepared on a large scale by the
Aelectrolysis of concentrated sodium chloride solution
Baction of manganese (IV) oxide on hot concentrated hydrochloric acid
Caction of concentrated tetraoxosulphate (IV) acid on sodium chloride
Doxidation of concentrated hydrochloric acid with potassium tetraxosulphate (VII)
Eaction of dilute mineral acids on bleaching powder
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Question 3
waec1985
Which of the following oxides is amphoteric?
ANa2O
BFe2O3
CAI2O3
DCaO
ECuO
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Question 4
jamb1985
Copper sulphate solution is electolysed using platinum electrodes A. current of 0.193 amperes is passed for 2hrs. How many grams of copper are deposited? (cu = 63.5, F = 96500 coulombs)
A0.457g
B0.500g
C0.882g
D0.914g
E1.00g
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Question 5
jamb1985
In what respect will two dry samples of nitrogen gas differ from each other if sample 1 is prepared by completely removing CO2 and O2 from air, and sample 2 is prepared by passing purified nitrogen(i)oxide over heated copper? sample 1 is
Apurer than sample 2
Bslightly denser than sample 2
Cin all respects the same as sample 2
Dcolourless but sample 2 has a light brown colour
Eslightly less reactive than sample 2
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Question 6
jamb1985
The boiling point of water, ethanol, toluene and butan-2-ol are 373.0k, 351.3k, 383.6k and 372.5k respectively. Which liquid has the highest vapour pressure at 323.0k?
Awater
Btoluene
Cethanol
Dbutan-2-ol
Enone
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Question 7
jamb1985
Hydrogen is not liberated when trioxonitrate(v)acid reacts with zinc because
Azinx is not rendered passive by acid
Bhydrogen produced is oxidized to water
Coxides of nitrogen are produced
Dall nitrates are soluble in water
Etrioxonitrate(v)acid is a strong acid
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Question 8
jamb1985
A certain volume of gas at 298k is heated such that its volume and pressure are now four times the original values. What is the new temperature?
A18.6k
B100.0k
C298.0k
D1192.0k
E4768.0k
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Question 9
jamb1985
Some properties of chemical substances are mentioned below... i. sour taste ii. slippery touch iii. yields alkaline gas with ammonium salt iv. has pH less than 7 v. turns phenolphthalein pink.
Which of the above are NOT typical properties of alkalis?
Ai, iv and v
Biv and v
Ci and iv
Dii and v
Eii, iii and iv
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Question 10
jamb1985
3.0g of a mixture of potassium carbonate and potassium chloride were dissolved were dissolved in a 250cm\(^3\) standard flask. 25cm\(^3\) of this solution required 40.00cm\(^3\) of 0.1M HCl for neutralization. What is the percentage by weight of K\(_2\)CO\(_3\) in the mixture ? (K = 39, O = 16, C = 12)
A60
B72
C82
D89
E92
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Question 11
jamb1985
Given that the molecular mass of iron is 56 and that of oxygen is 16, how many moles of iron(iii)oxide will be contained in 1kg of the compound?
A25.0 moles
B12.5 moless
C6.25 moles
D3.125 moles
E0.625 moles
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Question 12
jamb1985
Hydrogen diffuses through a porous plug
Aat the same rate as oxygen
Bat a slower rate than oxygen
Ctwice as fast as oxygen
Dthree times as fast as oxygen
Efour times as fast as oxygen
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Question 13
jamb1985
In the experiment, which of the following observations would suggest that a solid sample is a mixture? The
Asolid can be ground to a fine powder
Bdensity of the solid is 2.25gdm-3
Csolid begins to melt at 573k but is not completely melted until 648k
Dsolid absorbs moisture from the atmosphere and turns into liquid
Esolid melts at 300k
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Question 14
jamb1985
0.499g 0f CuSO4.xH2O when heated to constant weight gave a residue of 0.346g. the value of x is? (Cu = 63.5, S = 32.0, O = 16, H = 1)
A0.5
B2.0
C3.0
D4.0
E5.0
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Question 15
jamb1985
An organic compound contains 72% carbon, 12% hydrogen and 16% oxygen by mass. The empirical formula of the compound is
AC8H22O3
BC6H10O3
CC12H12O
DC6H12O
EC3H6O
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Question 16
jamb1985
Which of the following conduct electricity?
Asulfur
Bgraphite
Cdiamond
Dred phosphorus
Eyellow phosphorus
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Question 17
jamb1985
Use the following option above to answer this question. Which of the following is the functional group of carboxylic acids?
AA
BB
CC
DD
EE
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Question 18
jamb1985
The I.U.P.A.C name for the compound
A2-methyl-3-pentene
B4-methyl-2-pentane
C2-methyl-2-pentene
D4-methylpent-2-ene
E2-methyl-3-pentane
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Question 19
jamb1985
The oxidation of
A2-butanone
B2-butanal
Cbutane
Dbutanoic acid
E3-butanal
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Question 20
jamb1985
Use the above options to the question. The products formed on hydrolysis of
