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Question 1 Rapport
Sodium carbonate crystals on exposure to a dry atmosphere change to a white powder. This phenomenon is known as?
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Question 2 Rapport
Water is poured over a white solid and a colourless neutral gas is evolved which burns with a sooty flame. The white solid is?
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Question 3 Rapport
100 cm3 of oxygen is made to react with 50 cm 3 of hydrogen, and the whole reaction mixture was then passed through anhydrous calcium chloride. What is the volume of gas left?
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Question 4 Rapport
An element X has two isotopes, 2010X and 2010X,
present in the ratio 1:3. The relative atomic mass of X would be?
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Question 5 Rapport
When a solution of silver (l) nitrate is saturated with hydrogen sulphide, a black precipitate forms which is?
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Question 6 Rapport
Which of the following CANNOT be obtained by fractional distillation of petroleum?
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Question 8 Rapport
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)
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Question 10 Rapport
Which of the following types of reactions takes place between C2H4 and the halogens?
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Question 11 Rapport
If atom X with six electrons in its outermost shell combines with atom Y with one electron in its outermost shell to form an ionic compound, then?
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Question 12 Rapport
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 coulobms) (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.
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Question 15 Rapport
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
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Question 16 Rapport
9.8g of solid potassium chlorate (KCIO3) were added to 40 cm3 of water and heated to dissolve all the solid. As he solution cooled, crystals of potassium chlorate started forming at 60°C. The solubility of potassium chlorate at 66°C is therefore?
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Question 17 Rapport
A mixture contains 20cm3 of hydrogen, 35cm3 of oxygen, 15cm3 of carbon monoxide and 10cm3 of nitrogen at S.T.P. Which of the following gives the mole fraction of hydrogen in this mixture?
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Question 18 Rapport
When a pressure cooker is half filled with water, and heated to boiling point, then the pressure inside the cooker will?
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Question 19 Rapport
If the rate of diffusion of oxygen gas is taken as 1, what will be rated of diffusion of methane whose relative molar mass is 16?
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Question 21 Rapport
The nitrogen gas obtained by burning an excess of phosphorus in air has a density higher than the nitrogen from nitrogen compounds because the nitrogen from air is contaminated with?
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Question 22 Rapport
When air is passed through alkaline pyrogallol and then over quicklime, the only gases left are?
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Question 23 Rapport
Which of the following processes NOT lead to a chemical change?
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Question 24 Rapport
60cm3 of hydrogen are sparked with 20cm3 of oxygen at 100°C and 1 atmosphere. The total volume of the residual gases is?
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Question 25 Rapport
Which of the following statements is correct during the electrolysis of a caustic soda solution using platinum electrodes?
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Question 26 Rapport
In the chemical reaction A + B \(\to\) C + D, more of D is formed?
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Question 27 Rapport
How many grams of methylacetylene (propyne) CH3 — C Ξ CH will completely discharge the colour of 8g of bromine?
(Br = 80, C = 12, H = 1)
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Question 28 Rapport
The pressure on 100 cm3 of oxygen gas at 35°C is 750mm of Hg.What would be the volume of the gas if the pressure is increased to 1000mm of Hg without changing the temperature?
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Question 29 Rapport
Which of the following is a neutralization reaction? Addition of
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Question 30 Rapport
Which of the following combinations of conditions may increase the rate of a chemical reaction?
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Question 31 Rapport
Which of the following equations represents an oxidizing action of sulphur dioxide?
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Question 32 Rapport
The number of grammes of potassium hydroxide in 250cm3 of one molar solution is?
(K = 39, O = 16, H = 1)
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Question 33 Rapport
The product formed at the the cathode during the electrolysis of sodium chloride solution with carbon electrodes is?
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Question 34 Rapport
In the preparation of carbon monoxide by heating ethanedioic acid with concentrated sulphuric acid, the concentrated sulphuric acid act as?
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Question 35 Rapport
0.07g of a hydride of carbon occupies 56.0cm3 at S.T.P. when vaporized and contains 14.29% by mass of hydrocarbon is(C = 12, H = 1)
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Question 36 Rapport
What weight of sodium hydroxide is required to make 500 cm3 of 0.2 M solution?
(Na = 23, O = 16, H = 1)
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Question 38 Rapport
When a little brine was added to a metal nitrate a white precipitate was formed which first turned violet and then black on exposure to ai. The metal nitrate is therefore?
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Question 41 Rapport
In the reaction NH3 + H+ → NH4+, the bond formed results from?
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Question 42 Rapport
When copper powder is heated with concentrated sulphuric acid, the gas produced is?
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Question 43 Rapport
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?
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Question 44 Rapport
Which of the following bonds exist in crystalline ammonium chloride (NH4Cl)?
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Question 45 Rapport
The production of ammonia by the haber process may be represented by the equilibrium equation N2(g) + 3H2(g) ↔ 2NH3 ∆H = -22KJ. Therefore the production of ammonia will be favoured by?
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Question 46 Rapport
1.00 g of the oxide of metal X (atomic mass = 64) gave 0.80 g of the metal when reduced with hydrogen.
The formula of the oxide is?
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Question 47 Rapport
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)
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Question 49 Rapport
In the reaction N2(g) + O(g)
↔ 2NO(g) produced i an increase in the total pressure will?
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