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Which of the following represents a precipitation reaction?
AH2SO4 + NaCl \(\to\) NaHSO4 + HCl
BFe +H2SO4 \(\to\) FeSO4 + H2
C4HCl + MnO2 \(\to\) MnCl2 + 2H2O + Cl2
DNa2SO4 + pb(NO3) \(\to\) PbSO4 + 2NaNO
ECuO +2HCl \(\to\) Cl2 + H2O
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Question 2
jamb1981
The IUPAC name for
A1-methlpentane
B3-methylbutane
C2-methylbutane
D1-dimethylpropane
E2-methylpentane
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Question 3
jamb1981
The general formula of an alkyl halide (which represent the halide) is?
ACnH2n - 2X
BCnH2n + 1X
CCnH2n + 2X
DCnH2nX
ECnH2n - 1
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Question 4
jamb1981
An efflorescent compound is a substance that?
Aabsorbs water froom the air without dissolving in it
Bis capable of giving off coloured luminosity
Cgives out water to the atmosphere
Dabsorbs water from the air and dissolves in it
Egives out its water of crystallization on heating
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Question 5
jamb1981
The scale formation in a kinetic used for boiling water is caused by the presence in water of?
Acalcium sulphate
Bcalcium carbonate
Ccalcium hydrogen carbonate
Dcalcium hydroxide
Emagnesium sulphate
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Question 6
jamb1981
What happens when the nitrates of potassium, calcium, zinc and copper are separately heated?
AAll the nitrate will decompose to their respective metals
BThe nitrates of calcium and potassium will decomposes to their nitrites
COnly copper nitrate decomposes to the metal
DOnly the nitrates of zinc and copper will decompose to their oxides
EThe nitrates of calcium, zinc and copper decompose to their oxides
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Question 7
jamb1981
4g each of aluminium foil and aluminium powder were introduced respectively into flasks P and Q.
Flask P was treated with warm bench sodium hydroxide and all the aluminium dissolved in one hour. Flask Q was treated with cold sodium hydroxide and all the aluminium dissolved in 10 minutes. What was responsible for Q reacting faster than P?
AThere were more aluminium atoms in Q than P
BThe heat given off in retarded the reaction
CQ generated more pressure than P during the reaction
DP generated more pressure than Q
EQ has a greater surface area for the reaction than P
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Question 8
jamb1981
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 9
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 10
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 11
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 12
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 13
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 14
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 15
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 16
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 17
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 18
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 19
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 20
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?
