The reaction between sulphur (IV) oxide and oxygen is represented by the equilibrium reaction 2SO2(g) + O2(g) ↔ 2SO3(g), ∆H = -196 kJ. What factor would influence increased production of SO3(g)?
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(C)
Decrease in the temperature of the reaction
2
Magnesium ribbon was allowed to burn inside a given gas P leaving a white solid residue Q. Addition of water to Q liberated a gas which produced dense white fumes with a drop of hydrochloric acid. The gas P was?
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(A)
nitrogen
3
The best treatment for a student who accidentally poured concentrated tetraoxosulphate (VI) acid on his skin in the laboratory is to wash the skin with?
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(A)
cold water
4
In which of the following pairs of element is allotropy exhibited by each element?
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(D)
Oxygen and sulphur
5
Which of the following gases can best be used for demonstrating the fountain experiment?
i) Nitrogen (ii) Ammonia (iii) Nitrogen (I) oxide
(iv) Hydrogen chloride.
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(C)
ii and iv
6
When sodium hydroxide is heated with ammonium tetraoxosulphate (IV), the gas given off may be collected by?
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(C)
passing it directly through calcium oxide
7
Which of the following elements will form oxide which will dissolve both in dilute HNO3 and NaOH solutions to form salts?
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(A)
Al
8
Stainless steel is an alloy of?
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(C)
iron, carbon and chromium
9
Alloys are best prepared by?
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(D)
cooling a molten mixture of the necessary elements
10
Corrosion is exhibited by?
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(D)
all metals
11
Inspite of the electronic configuration, 1s22s22p2, carbon is tetraavalent because?
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(C)
both the 2s and 2p orbitals hybridizes
12
Which of the following compounds will give a precipitate with an aqueous ammoniacal solution of copper (l) chloride?
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(B)
CH3 ≡ CCH3
13
The efficiency of petrol as a fuel in high-compression internal combustion engines improves with an increase in the amount of?
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(A)
branched chain alkanes
14
Ethanol reacts with aqueous sodium mono-oxoio date (l) to give a bright yellow solid with a characteristic smell. The product is?
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(B)
triodomethane
15
The most volatile fraction obtained from fractional distillation of crude petroleum contains?
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(D)
methane, ethane and propane
16
Local black soap is made by boiling palm oil with liquid extract of ash. The function of the ash is to provide the?
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(C)
alkali
17
Synthetic rubber is made by polymerization of?
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(A)
2 methyl buta - 1, 3 - diene
18
Complete oxidation of propan -1- ol gives?
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(D)
propanoic acid
19
When water drops are added to calcium carbide in a container and the gas is passed through a jet and lifted, the resultant flame is called an?
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(C)
oxyacetylene flame
20
The greater the different in electronegativity between bonded atoms, the?
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(B)
higher the polarity of the bond
21
A stream of air was successively passed through three tubes X, Y and Z containing a concentrated aqueous solution of KOH, red hot copper powder and fused calcium chloride respectively. What was the composition of the gas emanating from tube Z?
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(D)
water vapour, N2 and the inert gases
22
In the purification of town water supply, alum is used principally to?
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(D)
coagulate small pasrticles of mud
23
Which of the following water samples will have the highest titre value when titrated for the Ca2+ ions using soap solution?
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(A)
Permanently hard water after boiling
24
Oil spillage in ponds and creeks can be cleaned up by?
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(B)
spraying with detergent
25
The solubility of Na3AsO4(H2O)12 is 38.9g per 100g H2O. What is the mass percentage of Na3AsO4 in the saturated solution?
(As = 75, Na = 23, O = 16, H = 1)
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(D)
13.7%
26
In which of the following are the aqueous solutions of each of the substances correctly arranged in order to decreasing acidity?
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(C)
Hydrochloride acid, ethanol acid, sodium chloride, milk of magnesia and sodium hydroxide
27
If 24.83 cm3 of 0.15 M NaOH is titrated to its end point with 39.45 cm3
of HCl, what is the molarity of the HCl?
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(A)
0.094 M
28
The atomic numbers of two elements X and Y are 12 and 19 respectively. The bond of these two elements is?
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(C)
Metallic
29
If d represents the density of a gas and K is a constant, the rate of gaseous diffusion r is related to d by the equation?
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(A)
r = k/√d
30
An isotope has an atomic number of 17 and a mass number of 36. Which of the following gives the correct number of neutrons and protons in an atom of the isotope?
