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1.00g of mixture of calcium carbonate and calcium oxide liberated 0.33g of carbon dioxide on strong heating. The percentage of calcium oxide in the mixture is? (Ca = 40, C = 12, O = 16)
A5
B15
C25
D35
E50
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Question 2
jamb1982
The i.u.p.A.C name for the compound
A2-chloro-isopentane
B3-chloro-isopentane
C2-chloro-2-methylbutane
D1-chloro-2,2- dimethylpropane
E2-chloro-2-ethylpropane
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Question 3
jamb1982
The solubility curve of a solid X (molecular mass = 160) is as show above. 1,000 cm3 of a saturated solution of X at 80°C is cooled to 40°C . The weight of X crystalized out would be
A10 g
B12 g
C14 g
D16 g
E18 g
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Question 4
jamb1982
60cm3 of hydrogen are sparked with 20cm3 of oxygen at 100°C and 1 atmosphere. The total volume of the residual gases is?
A60 cm3
B10 cm3
C40 cm3
D30 cm3
E70 cm3
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Question 5
jamb1982
The number of grammes of potassium hydroxide in 250cm3 of one molar solution is?
(K = 39, O = 16, H = 1)
A40g
B52g
C100g
D26g
E14g
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Question 6
jamb1982
Brass is an alloy containing copper and?
Azinc
Btin
Caluminium
Dsilver
Elead
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Question 7
jamb1982
Which of the following processes NOT lead to a chemical change?
AStrirring iron in sulphur (IV) acid
BStirring sodium carbonate in water
CStirring glucose in concentrated sulphur (IV) acid
DMixing sulphur (IV) acid with potassium carbonate
ETitrating an acid against base
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Question 8
jamb1982
0.16g of methane when burnt raises the temperature of 100g of water by 40°C. What is the of combustion of methane when if the heat capacity of water is 4.2 Jg-1°C-1?
(CH4 = 16)
A1,160 kJ mol-1
B1,180 kJ mol-1
C1,560 kJ mol-1
D1,600kJ mol-1
E1,680 kJ mol-1
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Question 9
jamb1982
Which of the following is NOT a redox reaction?
A2HNO2 + 2HI → 2H2O + 2NO + I2
BZn + H2SO4 → ZnSO4 + H2
CCa(HCO3)2 → CaCO3 + H2O + CO2
D4FeO + O2 → 2Fe2O3
E2Na + Cl2 → 2NaCl
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Question 10
jamb1982
Which of the following combinations of conditions may increase the rate of a chemical reaction?
ADecrease in temperature, increase in concentration of the reactants
BIncrease in temperature, addition of a catalyst, decrease in the surface area of the reactants
CIncrease in temperature, increase in concentration, addition of a catalyst and increase in the surface area of the reactants
DDecrease in temperature concentration and surface area of the reactants
EAdditionof a catalyst and in the absence of light
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Question 11
jamb1982
What weight of sodium hydroxide is required to make 500 cm\(^3\) of 0.2 M solution?
(Na = 23, O = 16, H = 1)
A40 g
B20 g
C10 g
D4 g
E2 g
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Question 12
jamb1982
How many grams of methylacetylene (propyne) CH\(_3\) — C Ξ CH will completely discharge the colour of 8g of bromine?
(Br = 80, C = 12, H = 1)
A0.5
B1.0
C2.0
D3.0
E4.0
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Question 13
jamb1982
Magnesium ribbon was added to each of the following aqueous solution in turn: H2SO4, AgNO3, HNO3, HCl, NH3, HCl, NH3. In which case does the magnesium become covered with a dark precipitate?
AH2SO4
BAgNO3
CHNO3
DNH3
EHCl
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Question 14
jamb1982
When copper powder is heated with concentrated sulphuric acid, the gas produced is?
Ahydrogen sulphide
Bsulphur dioxide
Csulphur trioxide
Dhydrogen pentasulphide
Esulphur pentoxide
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Question 15
jamb1982
In the preparation of carbon monoxide by heating ethanedioic acid with concentrated sulphuric acid, the concentrated sulphuric acid act as?
Aan oxidizing agent
Ba reducing agent
Ca dehydrating agent
Da reaction medium
Ea catalyst
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Question 16
jamb1982
A current of 10.0A was passed for 1 hour through a solution of copper (ll) sulphate between the copper electrodes. Which of the following observation would be correct?
(1 Faraday = 96,500 coulombs) (i) 0.186 mole of copper is dissolved from the anode. (ii) 0.372 mole of copper is deposited on the cathode. (iii) the original Cu2+ ion concentration of the solution remains unchanged. (iv) the original Cu2+ ion concentration of the solution decreases.
Ai and ii
Bi and iii
Ci and iv
Dii and iii
Eii and iv
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Question 17
jamb1982
Which of the following is a neutralization reaction? Addition of
Anitric acid to hydrochloric acid
Bnitric acid to sulphuric acid
Cnitric acid to distilled water
Dnitric acid to sodium hydroxide
Esodium chloride to distilled water
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Question 18
jamb1982
An element X has two isotopes, \(^{20} _{10}X\) and \(^{22} _{10}X\),
present in the ratio 1:3. The relative atomic mass of X would be?
A20.5
B21.0
C21.5
D22.0
E22.5
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Question 19
jamb1982
When a pressure cooker is half filled with water, and heated to boiling point, then the pressure inside the cooker will?
Adecrease, since only a fraction of the water molecules has changed to vapour
Bremain constant, because the total number of water molecules has not changed
Cincrease, because the water molecules can now reach every part of the sealed tube
Ddecrease, since water boils under reduced pressure
Eincrease, because the water vapour molecules now strike the walls of the tube more frequently because of their increased velocity
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Question 20
jamb1982
Which of the following bonds exist in crystalline ammonium chloride (NH4Cl)?
