The raw materials used for the smelting of iron ore in a furnace is
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(B)
CaCO3
2
On heating, which of the following compounds will decompose to the free metal, nitrogen (IV) oxide and oxygen?
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(C)
AgNO3
3
The group IA metals are not found free in nature because they
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(A)
are very reactive and unstable
4
Carbon exist naturally in the combined state as?
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(D)
wood
5
The efficiency of a solid catalyst to increase reaction rates depends on its
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(A)
surface area
6
Dynamic equilibrium describes a situation where
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(C)
both forward and reverse reactions proceed at the same rate
7
The ion that will give a white precipitate with aqueous NaOH and soluble in excess of the base is
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(C)
Zn2+
8
Which of the following pairs of substance will react further with oxygen to form a higher oxide?
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(D)
SO2 and NO
9
The characteristic colour of the flame shown when a copper salt moistened with concentrated hydrochloric acid on a platinum wire is put on bunsen burner is
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(B)
green
10
In the industrial production of H2 from natural gas the CO2 produced along with the H2 is removed by
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(A)
washing under pressure
11
The sulphide which is insoluble in dilute hydrochloric acid is
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(B)
CuS
12
Which of the following typically represents a photochemical reaction?
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(D)
Conversion of silver halides to grey metallic silver
13
The gas obtained as a product of anaerobic action on organic matter buried in the earth is?
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(B)
methane
14
Nigerian crude oil is described as light crude because of its
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(A)
low sulphur content
15
An example of aliphatic unsaturated hydrocarbon is
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(C)
propene
16
Which of the following has an isomer?
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(C)
C4H10
17
CH3 - CH2 - C≡CH
The hybridization in the compound above is
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(D)
sp3 and sp
18
One mole of a hydrocarbon contains 36g of carbon and its vapour density is 20. The structure of the hydrocarbon is
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(A)
CH3C ≡ CH
19
An emulsion may be produced by shaking a detergent solution with
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(C)
palm oil
20
The products of the combustion of candle wax are?
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(C)
carbon (IV) oxide and water
21
When 50cm\(^3\) of a saturated solution of sugar of molar mass 342 g at 40\(^o\)C was evaporated to dryness, 34.2g of dry solid was obtained. The solubility of sugar at 40\(^o\)C is
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(A)
2.0 mol dm-3
22
Which of the following results in the fall of acid rain?
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(C)
Oxides of sulphur
23
Water has the ability to dissolve almost all substance because its molecules has a structure with
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(B)
one positive end and one negative end
24
When a crystal was added to the clear solution of its salt, the crystal did not dissolve and the solution remained unchanged. This showed that the solution was
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(D)
saturated
25
A particle that contains 11 protons, 12 neutrons and 10 electrons is probably a
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(B)
metallic ion
26
A difference between chemical and physical change is that in a chemical change
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(D)
a new substance is formed
27
The volume of 2.5 moles of oxygen at s.t.p is
[Molar volume of a gas at s.t.p = 22.4 dm3]
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(D)
56.0 dm3
28
Nuclear fission involves the splitting of a heavy element into two nuclei of
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(A)
nearly equal masses with a release of energy and radiation
29
What is the molar mass of a substance, if 0.4 mole of the substance has a mass of 25.0g?
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(A)
62.5 g
30
The element with the electron configuration 1S\(^2\)2S\(^2\)2P\(^3\) is
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(D)
nitrogen
31
A decrease in atomic size and an increase in nuclear charge across a period lead to
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(C)
a decrease in electropositivity
32
The order in which a mixture of sand, ammonium chloride and sodium chloride can be separated is
If 30cm\(^3\) of gas at 50\(^0\)C is warmed to 80\(^0\)C at a fixed pressure, the fractional increase in volume is
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(B)
0.093
35
2C\(_2\)H\(_2\)(g) + 5O\(_2\)(g) → 4CO\(_2\)(g) + 2H\(_2\)O(g)
In the reaction above, the mass of carbon(IV)oxide produced on burning 78 g of ethyne is
[C =12, O = 16, H = 1]
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(A)
264 g
36
The ion that can be used as an oxidizing agent is
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(C)
ClO-
37
H\(_2\)(g) + Br\(_2\)(g) → 2HBr(g)
The above reaction is carried out at 25\(^0\)C. ΔH is -72 kJ mol-1 and ΔS is - 106 J mol-1K-1, the reaction will?
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(B)
proceed spontaneously at the given temperature
38
Zinc and carbon rods are used as anode and cathode respectively in a
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(A)
Leclanche cell
39
The solution that will conduct the highest amount of electricity is?
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(B)
2.0 mol dm-3 of hydrochloric acid
40
In which of the following is the oxidation number of sulphur equal to - 2?
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(C)
H2S
41
In the electrolysis of CuSO\(_4\)(g) using platinum electrodes, the reaction at the anode is
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(B)
4OH- + 4e- → 2H2O + O2
42
Na\(_2\)CO\(_3\)(g) + 2HCl(aq) → 2NaCl(aq) + H\(_2\)O(l) + CO\(_2\)(g)
How many moles of sodium trioxocarbonate (IV) are there in a 25 cm\(^3\) solution which required 10cm\(^3\) of 0.05 mol dm\(^3\) hydrochloric acid solution to neutralize it?
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(C)
0.010 mole`
43
If the heat of combustion of hydrogen is -285.8kJ,
What is the heat of formation of water?
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(C)
-285.8 kJ
44
5SO\(_2\)(g) + 2KMnO\(_4\)(aq) + 2H\(_2\)O(l) → K\(_2\)SO\(_4\) + 2MnSO\(_4\)(aq) + 2H\(_2\)SO\(_4\)(aq)
In the reaction above, the products give a
