JAMB UTME - Chemistry - 1978

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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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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Consider the following equation H₂O + 2Fe²⁺ + Cl₂ ↔ 2Fe³⁺ + 2Cl^- + H₂O. The only ion which behaves as an oxidising agent is

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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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Hypochlorous acid is used as a bleach because

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By means of filtration, one component can be obtained pure from an aqueous mixture of sodium chloride and

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Which of the following gases may not be dried with concentrated sulphuric acid?

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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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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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Which of the following compounds will form a solution if exposed to air?

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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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An element X forms the following compounds with chlorine; XCl₄, XCl₃, XCl₂. This illustrates the

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Which of the following is not a member of the homologous series of the paraffins (alkanes)?

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When heat is absorbed during a chemical reaction, the reaction is said to be

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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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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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The IUPAC names of the compounds CH3COOH and CH2=CH2 are respectively;

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The pH of four solutions W, X, Y, Z are 4, 6, 8, 10 respectively, therefore

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Zinc Oxide is a

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The normal boiling point of a liquid is defined as

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When sodium chloride and metallic sodium are each dissolved in water

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Which of the following metals cannot replace hydrogen from water or steam?

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Consider the following exothermic reaction
2SO_2(g) + O_2(g) ↔ 2SO_3(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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The reaction between an organic acid and an alcohol in the presence of an acid catalyst is known as;

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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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Elements P, Q, R, S have 6, 11, 15, 17 electrons respectively, therefore,

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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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The oxidation state of chlorine in potassium chlorate is

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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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In titration involving sodium hydroxide and dilute hydrochloric acid, where would you place the base?

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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 100^oC, which solution or solutions will deposit 100 g of the solute when suddenly cooled to 0^oC?

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An example of an alcohol is

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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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The nucleus of an atom contains

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Brass and bronze are both metallic alloys. Which of the following constituents is common to both alloys?

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The most common type of chemical reaction which alkanes undergo is

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Which of the following reactions does not take place in the smelting of iron in a blast furnace?

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When each of the nitrates of Potassium, Magnesium and iron is heated,

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Which of the following changes is physical?

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The periodic classification of elements is an arrangement of the elements in order of their

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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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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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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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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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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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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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During the electrolysis of copper II sulphate between platinum electrodes, if litmus solution is added to the anode compartment,

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When ammonia and hydrogen ion bond together to form ammonium ion, the bond formed is called

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