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Question 1 Rapport
What reaction takes place when palm-oil is added to potash and foam are observed?
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Question 2 Rapport
Which of the following are made by the process of polymerization?
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Question 3 Rapport
The reaction Mg + H2O → MgO + H2 takes place only in the presence of?
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Question 4 Rapport
Which of the following metals does NOT form a stable trioxocarbonate (IV)?
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Question 5 Rapport
Which of the following is used as an 'anti-knock' in automobile engines?
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Question 7 Rapport
Use the options above to answer this question. Which is the structural formula for pent-2-enoic acid?
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Question 8 Rapport
The iron (III) oxide impurity in bauxite can be removed by?
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Question 9 Rapport
The movement of liquid molecules from the surface of the liquid to the gaseous phase above it is known as?
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Question 10 Rapport
Which of the following groups of physical properties increases from left to right of the periodic table? i. Ionization energy ii. Atomic radius iii. Electronegativity iv. Electro affinity
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Question 12 Rapport
20 cm3 of 1.0 molar NH4OH solution when neutralized with 20.05cm3 of 0.1 molar HCl liberated -102 joules of heat. Calculate the heat of neutralization of NH4OH?
Détails de la réponse
NH4OH = 20cm of 0.1 m
NH4 + HCl → NH4Cl = H2O
Heat of Neutralization of NH4OH
= −1022
= -51.0 KJ mole-1
Question 13 Rapport
In the solubility curve above, water at 98oC is saturated with KCL and KCIO3 What is the percentage of KCL impurity in the crystals formed when the solution is cooled to 30 oC?
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Question 14 Rapport
The exhaust fumes from a garage in a place that uses petrol of high sulphur content are bound to contain?
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Question 15 Rapport
Which of the following does NOT contain aluminium as component?
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Question 17 Rapport
Which of the following is NOT correct test for the named organic compound in each case?
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Question 18 Rapport
How will a metal X, which reacts explosively with air and with dilute acids be best extracted from its ores?
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Question 19 Rapport
In the electrolysis of aqueous solution of K2SO 4 in the above cell, which species migrate to the anode?
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Question 21 Rapport
The tabulated results below were obtained by titration 10.0 cm3 of water with soup. The titration was repeated with the same sample of water after boiling. The ratio of permanent to temporary hardness is
Détails de la réponse
The ratio of permanent to temporary hardness will be 20:(20 - 15)
= 20:5
= 4:1
Question 22 Rapport
Which of the following compounds is NOT formed by the action of chlorine on methane?
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Question 24 Rapport
What is the consequences of increasing pressure on the equilibrium reaction ZnO(s) + H2(g) Zn(s) + H2O(I)?
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Question 25 Rapport
The number of atoms of chlorine present in 5.85g of NaCl is [Avogaro's Number = 6.02 x 1023]
Détails de la réponse
The number of atoms of chloride present in 5.85g of NaCl is 5.85 x 6.0 x 1023
= 6.02 x 1022
Question 27 Rapport
Which of the following solutions will conduct the least amount of electricity?
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Question 28 Rapport
10cm3 of hydrogen fluoride gas react with 5cm3 of dinitrogen difluoride gas (N2F2) to form 103 of a single gas. Which of the following is the most likely equation of the reaction?
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Question 29 Rapport
Which of the following will react further with oxygen to form higher oxide?
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Question 30 Rapport
Which of the following salts when dissolved in water will NOT give the corresponding pH value?
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Question 31 Rapport
Which of the following sulphides is insoluble in dilute HCl?
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Question 32 Rapport
The general formula of an alkyl halide (where X represents the halide) is?
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Question 33 Rapport
When steam is passed through red hot carbon, which of the following are produced?
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Question 34 Rapport
What are the values of x, y and z respectively in the equation: xCu + yHNO3 ? xCu(NO3)2 + 4H2O + zNO?
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Question 35 Rapport
Which of the following compounds would give lilac flame coloration and a white precipitate with acidified barium chloride solution?
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Question 36 Rapport
When ethanol is heated with excess concentrated sulphuric acid, the ethanol is?
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Question 37 Rapport
A substance Z reacts with NaOH to give salt and water only. When Z is treated with dilute HCl, a gas is evolved which gives a yellow suspension on passing into concentrated H2SO4. Substance Z is?
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Question 38 Rapport
The relationship between the velocity (U) of gas molecules and their relative molecular mass (M) is shown by the equation
Détails de la réponse
The relationship between (U) of a gas molecule and the relative molecular mass is ¯U = (km )12
or ¯U = √km
Question 39 Rapport
When chlorine is passed into water and subsequently exposed to sunlight, the gas evolved is?
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Question 40 Rapport
Oxygen-demanding waste are considered to be a water pollutant because they?
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Question 41 Rapport
A white solid suspected to be lead trioxonitrate (V) zinc trioxocarbonate (IV) or calcium trioxocabonate (IV) was heated strongly. Its residue which was yellow when hot and white when cold is?
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Question 42 Rapport
The approximate volume of air containing 10cm3 of oxygen is?
Détails de la réponse
Volume of air containing 10 cm O2 is
(100 x 10)/(20) = 50cm3
Question 43 Rapport
In the course of an experiment, two gases X and Y were produced. X turned wet lead ethanoate to black and Y bleached moist litmus paper. What are the element(s) in each of the gases X and Y respectively?
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Question 44 Rapport
How much of magnesium is required to react with 260cm3 of 0.5 M HCl? [Mg = 24]
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Question 45 Rapport
What mass of a divalent metal M (atomic mass = 40) would react with excess hydrogen gas measured at S.T.P?
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Question 46 Rapport
How many coulombs of electricity are passed through a solution in which 6.5 amperes are allowed to run for 1.0 hour?
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Question 47 Rapport
When 50cm3 of a saturated solution of sugar (molar mass 342.0g) at 40oC was evaporated to dryness, 34.2g of dry solid was obtained. The solubility of sugar at 40oC is
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