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If one mole of aluminium contains 6 x 1023 atoms of aluminium, how many atoms are contained in 0.9g of aluminium?
(Al = 27)
A1.0 x 1021
B6.6 x 1021
C2.0 x 1022
D1.0 x 1022
E5.4 x 1023
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Question 2062
jamb1981
Which one of the following metals is not normally extracted by chemical reduction because of its position in the electrochemical series?
ACopper
BIron
CLead
DPotassium
EZinc
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Question 2063
jamb1981
When hydrogen sulphide and sulphur dioxide are each passed in turn into a solution of potassium dichromate?
Aboth gases change the colour of the solution from yellow to colourless
Bboth gases causes sulphur to be deposited
Conly hydrogen sulphide decolourizes the solution
Donly sulphur dioxide deposits sulphur
Eonly hydrogen sulphide deposits sulphur
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Question 2064
jamb1981
Which of the following compounds and elements would sublime on exposure to the atmosphere?
AIce
BSulphur
CPhosphurous
DIodine
EPotassium iodie
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Question 2065
jamb1981
What mass of sodium carbonate solution is in 500 cm3 of 0.1 molar sodium carbonate solution?
(Na = 23, C = 12, O = 16)
A10.6 g
B5.3 g
C500 g
D10 g
E20 g
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Question 2066
jamb1981
Pure sulfuric acid is a liquid of 1.84 density. What volume of it would be required to prepare 250 cm3 of 2.0 M solution?
(H = 1, S = 32, O = 16)
A2.00
B2.66
C3.00
D3.66
E4.00
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Question 2067
jamb1981
In the extraction of iron, which of the following reactions does NOT take place in the blast furnace?
ACO2 + C → 2CO
B2Fe2O3 + 3C → 4Fe + 3CO2
CFe2O3 + 3CO → 2Fe + 3CO2
DCaCO3 → CaO + CO2
ECaO + SiO2 → CaSiO3
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Question 2068
jamb1981
5cm3 of a saturated solution of sodium chloride at 30°C gave, on careful evaporation, 1.95g of solid salt. The solubility of sodium chloride at 30°C?
(Na = 23, Cl = 35.5)
A5.00 mole dm3
B5.67 mole dm3
C6.00 mole dm3
D6.67 mole dm3
E7.00 mole dm3
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Question 2069
jamb1981
The electronic configuration of elements X and Y are X = 2, 8, 6; Y = 2, 8, 7. The bond in the compound formed by X and Y is expected to be?
Aionic
Bcovalent
Cdative covalent
Dmetallic
Enone of the above
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Question 2070
jamb1981
Which of the following is NOT a true statement of the kinetic Theory of Gases?
AThe molecules move at random
BThe size of molecules is negligble as compared with the volume of gas
CThe molecular collisions are perfectly elastic
DEvery molecule has the same kinetic energy at a particular temperature
EThe average kinetic energy is proportional to the absolute temperature of the gas
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Question 2071
jamb1981
The products of the reaction between dilute sulphuric acid and sodium thiosulphate crystals are?
ANa2SO4 + SO2 + O2 + H2O
BNa2SO3 + SO3 + O2 + H2O
CNa2SO4 + SO2 + S + H2O
DNa2SO4 + SO3 + S + H2O
ENa2SO4 + SO2 + H2O only
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Question 2072
jamb1981
The following compounds are given with their corresponding boiling points.
Compound Boiling Point
i.................................14°C
ii................................24°C
iii................................0°C
iv................................120°C
V.................................-2°C
From the above information, indicate which of the following is correct?
AAll the compounds are gaseous at 20 °C
BOne of the compounds is gaseous at 20 °C
CTwo of the compounds are gaseous at 20 °C
DThree of the compounds are gaseous at 20 °C
ENone of the compounds is gaseous at 20 °C
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Question 2073
jamb1981
If 48,000 coulombs of electricity are required to discharge 0.5 mole of sodium from a molten sodium chloride mass, then the number of coulombs required to discharge 2 moles of lead from molten lead (ll) chloride is?
A48,000
B96,000
C192,000
D384,000
E576,000
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Question 2074
jamb1981
28.8 cm3 of nitrogen at 15°C is cooled to O°C at constant pressure, the new volume of nitrogen is?
A17.4 cm3
B14.7 cm3
C27.3 cm3
D31.7 cm3
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Question 2075
jamb1981
Which of the following statements about phosphorus is NOT correct?
APhosphorus is a solid mineral
BPhosphorus is obtained by oxidation reaction of phosphate
CPhosphorus exists in two allotropic forms
DBoth forms of phosphorus are interconvertible
EYellow phosporus ignites when rubbed on a rough surface
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Question 2076
jamb1981
Fats and oils are?
Aaddition products of long chain fatty acids and alkali
Baddition products of long-chain fattyy acids and glycerol
Ccondensation products of long-chain fatty acids and glycerol
Dcondensation products of formaldehyde and glycerol
Eliquids at 20°C
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Question 2077
jamb1981
When air is compressed?
Aits density decreases
Bit solidifies
Cits temperature decreases
Dits temperature increases
Eits temperature remains unchanged
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Question 2078
jamb1981
If an organic compound decolorizes bromine water then the compound is?
Asaturated
Bsupersaturated
Cunsaturated
Da solid
Eprotonated
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Question 2079
jamb1981
When sodium nitrate dissolves in water, ∆H is positive. This means that?
Athe reaction is catalysed
Bthe reaction is complete
Cthe reaction is exothermic
Dthe reaction is endthermic
Esodium nitrate is highly soluble in water
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Question 2080
jamb1981
Na2CO3 + 2HCI → 2NaCI + H2O + CO2. Using the above equation, what volume of carbondioxide, measured at s.t.p is liberated when 53g of sodium carbonate is dissolved in hydrochloric acid?
(1 mole of gas occupies 22.4 dm3 at s.t.p)
(Na = 23, C = 12, O = 16)
