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Question 1 Rapport
By means of filtration, one component can be obtained pure from an aqueous mixture of sodium chloride and
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Question 2 Rapport
Five compounds R,T,W,X and Y form the following compounds: a basic hydride R.H, an acidic hydride YH, atmospheric oxide W2O3, XO2. which of the elements is an alkali
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Question 4 Rapport
Which of the following reactions does not take place in the smelting of iron in a blast furnace?
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Question 5 Rapport
An element X forms the following compounds with chlorine; XCl4, XCl3, XCl2. This illustrates the
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Question 6 Rapport
A solid X when heated gives off a brown gas. If X is soluble in excess sodium hydroxide solution but insoluble in excess ammonium hydroxide solution, then X is
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Question 7 Rapport
Two gas cylinders contain ethylene (ethene) and acetylene respectively. One test which can be used to distinguish between them is by
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Question 8 Rapport
Three solutions contain carbonate, sulphate and sulphide ions respectively. One test that will identify just ONE of them completely is by addition to each of them of
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Question 9 Rapport
The most common type of chemical reaction which alkanes undergo is
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Question 10 Rapport
In the reaction between sodium hydroxide and sulphuric acid solutions, what volume of 0.5 molar sodium hydroxide would exactly neutralise 10cm3 of 1.25 molar sulphuric acid?
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Question 11 Rapport
During the electrolysis of copper II sulphate between platinum electrodes, if litmus solution is added to the anode compartment,
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Question 13 Rapport
A small quantity of solid ammonium chloride (NH4Cl) was heated gently in a test tube, the solid gradually disappears to produce two gases. Later, a white cloudy deposit was observed on the cooler part of the test tube. The ammonium chloride is said to have undergone
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Question 15 Rapport
Consider the solubility curves of three salts X, Y and Z given in the diagram. If each solution of the salt contains 200 g, and is heated to 100oC, which solution or solutions will deposit 100 g of the solute when suddenly cooled to 0oC?
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Question 16 Rapport
Consider the following exothermic reaction
2SO2(g) + O2(g) ↔ 2SO3(g)
If the temperature of the reaction is reduced from 800°C to 500°C, an no other change takes place, then
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Question 17 Rapport
The periodic classification of elements is an arrangement of the elements in order of their
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Question 18 Rapport
Which of the following substances would you see as an indicator in the titration of sodium carbonate solution against hydrochloric acid (complete neutralisation)?
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Question 19 Rapport
When sodium chloride and metallic sodium are each dissolved in water
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Question 20 Rapport
When ammonia and hydrogen ion bond together to form ammonium ion, the bond formed is called
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Question 21 Rapport
When air which contains the gases Oxygen, nitrogen, carbondioxide, water vapour and the rare gases, is passed through alkaline pyrogallol and then over quicklime, the only gases left are;
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Question 22 Rapport
Which of the following metals cannot replace hydrogen from water or steam?
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Question 23 Rapport
A sample of hard water contains some calcium sulphate and calcium hydrogen carbonate. The total hardness may therefore be removed by
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Question 24 Rapport
Which of the following compounds will form a solution if exposed to air?
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Question 25 Rapport
You are provided with five gas jars containing SO2, CO2, H2, CO and NO respectively. Select a test from A to E which will identify ANY ONE of the gases completely
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Question 26 Rapport
A gas jar was inverted over burning yellow phosphorus floating over water in a beaker. After burning, the water level was found to rise in the gas jar. The water level rises because
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Question 27 Rapport
Brass and bronze are both metallic alloys. Which of the following constituents is common to both alloys?
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Question 28 Rapport
Which of the following gases may not be dried with concentrated sulphuric acid?
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Question 29 Rapport
Which of the following is not a member of the homologous series of the paraffins (alkanes)?
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Question 30 Rapport
If hydrogen sulphide gas is passed into a solution of a pure iron chloride, a yellow deposit appears. If the deposit is filtered, a pale green solution is left behind. The pale green solution is
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Question 32 Rapport
If excess zinc is added to a bluish green solution of copper (II) sulphate, and the excess zinc filtered off after completion of reaction, a colourless solution is obtained because
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Question 33 Rapport
The reaction between an organic acid and an alcohol in the presence of an acid catalyst is known as;
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Question 35 Rapport
An experiment test of the Law of conservation of Mass is illustrated in the diagram. In practice, the flask is weighed before and after reaction between solutions X and Y. Which of the following pairs of solutions will be unsuitable for the experiments
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Question 36 Rapport
When large hydrocarbon molecules are heated at high temperature in the presence of a catalyst to give smaller molecules, the process is known as
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Question 37 Rapport
The pH of four solutions W, X, Y, Z are 4, 6, 8, 10 respectively, therefore
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Question 39 Rapport
Consider the following equation H2O + 2Fe2+ + Cl2 ↔ 2Fe3+ + 2Cl- + H2O. The only ion which behaves as an oxidising agent is
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Question 40 Rapport
When each of the nitrates of Potassium, Magnesium and iron is heated,
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Question 41 Rapport
The IUPAC names of the compounds CH3COOH and CH2=CH2 are respectively;
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Question 42 Rapport
Which of the five atoms can be described by the following properties: Relative atomic mass is greater than 30 but less than 40, it has odd atomic number and forms a unipositive ion in solution?
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Question 43 Rapport
Elements P, Q, R, S have 6, 11, 15, 17 electrons respectively, therefore,
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Question 44 Rapport
The size (diameter) of five elements are in the order R < T < W < X < Y, Y being the largest. If each atom has an electron situated on its circumference, and neglecting other factors, which of the atoms will lose its electron most reluctantly?
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Question 46 Rapport
In titration involving sodium hydroxide and dilute hydrochloric acid, where would you place the base?
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Question 47 Rapport
If 30cm3 of oxygen diffuses through a porous pot in 7 seconds, how long will it take 60cm3 of chlorine to diffuse through the same pot, if the vapour densities of oxygen and chlorine are 16 and 36 respectively?
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Question 48 Rapport
When heat is absorbed during a chemical reaction, the reaction is said to be
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