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In the experiment above, ammonium chloride crystals deposit on the walls of the tube is as a result of
Aevaporation
Brecrystallization
Csublimation
Dfractional precipitation
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Question 1002
jamb1988
An eruption pollution an environment with gas suspected to be H2S, a poisonous gas. A residue team should spray the environment with?
Awater
Bmoist SO2
Cacidified KMnO4 and water
Dwater, acidified KMnO4 and oxygen
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Question 1003
jamb1988
The molar ratio of oxygen to nitrogen in dissolved air is 2:1 whereas the ratio is 4:1 in atmospheric air because?
Anitrogen is less soluble than oxygen
Boxygen is heavier than nitrogen
Cnitrogen has a higher partial pressure in air
Dgases are hydrated in water
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Question 1004
jamb1988
The energy changes accompanying the addition of an electron to a gaseous atom is called?
Afirst ionization energy
Bsecond ionization energy
Celectron affinity
Delectronegativity
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Question 1005
jamb1988
What are the possible oxidation numbers of an element if its atomic number is 17?
A-1 and 7
B-1 and 6
C-3 and 5
D-2 and 6
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Question 1006
jamb1988
Which of the following physical properties decreases across the Periodic Table?
AIonization potenial
BElectron affinity
CElectronegativity
DAtomic radius
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Question 1007
jamb1988
A metallic ion X2+ with an inert gas structure contains 18 electrons. How many protons are there in this ion?
A20
B18
C16
D2
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Question 1008
jamb1988
The forces holding naphthalene crystals together can be overcome when naphthalene is heated to a temperature of 354K resulting in the crystal to melting. These forces are known as?
Acoulombic
Bionic
Ccovalent
DVan der waals
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Question 1009
jamb1988
An increase in temperature causes an increase in the pressure of a gas because there is an increase in the?
Aaverage velocity of the molecules
Bnumber of collisions between the molecules
Cdensity of the molecules
Dfree mean path between each molecules and other
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Question 1010
jamb1988
One mole of propane is mixed with five moles of oxygen. The mixture is ignited and the propane burns completely. What is the volume of the products at s.t.p?
(G.M.V = 22.4 dm3 mol-1)
A112.0 dm3
B67.2 dm3
C56.0 dm3
D44.8 dm3
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Question 1011
jamb1988
2.25g of a sample of an oxide of copper on reduction gave 2.0g of copper. 2.50g of another oxide of copper on reduction also gave 2.0g of copper. These results are in accordance with the law of?
Aconstant composition
Bconservation of matter
Cmultiple proportions
Ddefinite proportions
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Question 1012
jamb1988
The formula of a compound formed in a reaction between a trivalent metal M and a tetravalent non-metal X is~?
AMX
BM3X4
CM4X3
DM3X2
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Question 1013
jamb1988
What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?
ASteam distillation
BDestructive distillation
CLiquefaction
DHydrolysis
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Question 1014
jamb1988
Detergents have the general formula?
AR(CH2)nOH
BRSO3-Na+
CRSO-2Na+
DRSO2H
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Question 1015
jamb1988
Which of the following compounds has the highest boiling point?
ACH3CH2CH2CH2HO
BCH3CH2CH2CHO
CCH3CH2CH2CH3
DCH3CH2OCH2CH3
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Question 1016
jamb1988
The four classes of hydrocarbons are?
Aethane, ethene, ethyne and benzene
Balkanes, alkenes, alkynes and aromatics
Calkanes, alkenes, alkynes and benzene
Dmethane, ethane , propane and butane
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Question 1017
jamb1988
Alkanoates are formed by the reaction of alkanoic acid with?
AAlkyl halides
Balkanols
Cethers
Dsodium
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Question 1018
jamb1988
Methylethanoate reacts with ammonia to yield?
Amettylamine and ethanol
Bethylamine and methanol
Cmethanamide and ethanol
Dethanamide and methanol
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Question 1019
jamb1988
Crude copper can be purified by the electrolysis of CuSO4(aq) if?
Aplatinum electrodes are used
Bthe crude copper is made the anode of the cell
Cthe crude copper is made the cathode of the cell
Dcrude copper electrodes are used
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Question 1020
jamb1988
Given the reactions (i) Fe(s) + X(NO3)2(aq) → Fe(NO3) + X(s) (ii) H2(g) + XO
