JAMB UTME - Chemistry - 1978

Zinc Oxide is a

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

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

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

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

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

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Which of the following changes is physical?

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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 substances would you see as an indicator in the titration of sodium carbonate solution against hydrochloric acid (complete neutralisation)?

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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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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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Hypochlorous acid is used as a bleach because

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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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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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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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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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The reaction between an organic acid and an alcohol in the presence of an acid catalyst is known as;

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

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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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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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An example of an alcohol is

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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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The nucleus of an atom contains

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

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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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The most common type of chemical reaction which alkanes undergo is

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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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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 compounds will form a solution if exposed to air?

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

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

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The IUPAC names of the compounds CH3COOH and CH2=CH2 are respectively acetic acid and ethene. Acetic acid is a carboxylic acid with the formula CH3COOH, while ethene is an unsaturated hydrocarbon with the formula CH2=CH2. The IUPAC naming system is a set of rules used to give unique names to organic compounds based on their molecular structure. In this case, the IUPAC name of CH3COOH is derived from the parent alkane, which is methane (CH4). Replacing one hydrogen atom in methane with a methyl group (CH3) results in the parent chain for acetic acid, which is ethane (C2H6). The carboxyl group (-COOH) attached to the second carbon atom in the chain gives the compound its name, ethanoic acid. Similarly, the IUPAC name of CH2=CH2 is ethene, which is derived from the parent alkane, ethane, by removing one hydrogen atom from each of the two carbon atoms that form a double bond.

When sodium chloride and metallic sodium are each dissolved in water

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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 normal boiling point of a liquid is defined as

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

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

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

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The oxidation state of chlorine in potassium chlorate 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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