23/04/2020 Senior Class WAEC/NECO/UTME Mock Exams(Chemistry) 23/04/2020 0Comments by Gate Academy Please, fill out the information below to continue. NAME EMAIL PHONE NUMBER 1. The isotope of hydrogen with relative atomic mass of 2 is? Tritium Protium Hydride Deuterium 2. Hydrogen can be found in these substances except? Limestone Alkalis Acids Natural Gas 3. RDX is chemical compound. How is it used? As an nuclear weapon As an explosive As an composition As an reactor 4. Where are Bio-chemical compounds used? Food preservatives All of the above Cooking Oils Skin Treatments 5. Which of the following decreases when a given mass of gas is compressed to half its initial volume? Atomic radius of each particle Average intermolecular distance Number of molecules present Frequency of collisions 6. 15dm³ of a gas at s.t.p. in a tube was pressed by a piston whose pressure was increased to twice its original value at the same temperature. The volume of the gas in dm³ at this new pressure is 12.0dm³ 10.0dm³ 7.5dm³ 5.0dm³ 30.0dm³ 7. CuSO4.5H2O can be obtained from an aqueous solution of copper(ii)tetraoxosulphate(vi) by Using chromatography Precipitation Evaporation to dryness Crystallization 8. Freshly boiled tap water tastes different from ordinary tap water because it contains more carbon(iv)oxide it contains less dissolved air the water molecules are now smaller all the germs have been killed it contains more dissolved oxygen 9. In which form is natural petroleum found? Tar Kerosene Gasoline Crude Oil 10. In the reaction, E + F ↔ G + H, the backward reaction is favoured if the concentration of F is increased G is reduced E is increased E is reduced 11. P, Q, R, S are metals in the same period in the periodic table but in groups 3, 4, 5, 6 respectively. Which of them loses electrons least reactively? R P S Q 12. A synthetic rubber is having__________weight. Higher atomic Higher resistance Lower density Higher molecular 13. Most commonly used Rodenticides are _______ in nature. Anti pesticides Anti solvent Non anti coagulant Anti Coagulant 14. What current in amperes will deposit 2.7g of aluminium in 2 hours?[Al = 27, 1F = 96500C] 28 8 32 16 4 15. Chemistry is a branch of science which can be used for providing the services to mankind. Comment on the statement. Strongly not False True May Be 16. The following metals are usually extracted by the method of electrolysis EXCEPT magnesium potassium iron aluminium sodium 17. What term is used to describe an oxide whose aqueous solution turns blue litmus red Amphoteric oxide Basic oxide Strong electrolyte Acid anydride 18. When an atom gains an electron, it becomes An anion Positively charged A non-metal atom Chemically inactive A cation 19. The following are diatomic except? Nitrogen Helium Fluorine Hyrdrogen 20. Which of these is not a property of a system that is in a state of chemical equilibrium? It must take place in a closed system It is a reversible system The change in entropy is zero The value of change in free energy is zero 21. What will be the effect of increase in pressure on the following system at equilibrium?2NH3(g) ↔ N2(g) + 3H2(g) The concentration of ammonia will increase The forward reaction will be favoured Activation energy will decrease The reaction will go to completion 22. What property of hydrogen makes it suitable for filling balloons? Its flammability Its tensile strength Its low density Its solubility 23. Example(s) of colloids include:I. emulsionsII. solsIII. FogIV. smoke III and IV Only I, II and III Only IV Only I, II, III and IV I and II Only 24. The following salts can be prepared by a double decomposition reaction EXCEPT BaSO4 KCl PbCl2 BaCO3 AgCl 25. A feasible cell was constructed by joining the two half cells below:Cu2+ (aq) + 2e- → Cu(s); Eꝋ = + 0.34vZn2+ (aq) + 2e- → Zn(s); Eꝋ = - 0.76vWhat is the standard e.m.f of the cell? - 1.1v - 0.42v + 0.42v + 1.1v 26. When ammonium chloride is dissolved in water in a test tube, the test tube feels cooler showing that? Ammonia gas is evolved The process is endothermic The solution is unsaturated Sublimation has occurred 27. Which of the following is NOT a halogen? silicon astatine iodine bromine fluorine 28. What volume of propane is left unreacted when 20cm³ of oxygen reacts with 20cm³ of propane? 1cm³ 20cm³ 40cm³ 5cm³ 16cm³ 29. If a metal R forms a compound with the formula R(NO3)2 , the formula of its tetraoxosulphate(vi) is? R(SO4)2 RSO4 R2SO4 R2(SO4)3 30. When hydrogen sulphide gas is passed through an acidified solution of potassium heptaoxo dichromate(vi), the orange colour changes to green. This is because the chromium(vi) ion is oxidized sulphide ion changes to sulphur atom +3 state of Cr is oxidized to +6 state hydrogen sulphide is a good oxidizing agent +6 state of Cr is reduced to +3 state 31. Which of the listed molecules has two lone pairs of electrons? carbon(iv)oxide water benzene ammonia hydrogen gas 32. Which is not used as an alkali? Potassium hydroxide Sodium hydroxide Carbon hydroxide Nitrogen hydroxide 33. What mass of water is produced when 8.0g of hydrogen reacts with excess oxygen?[H=1, O=16] 72.0g 8.0g 36.0g 54.0g 34. Dilute HCl produces a gas with each of the following compounds EXCEPT sodium trioxosulphate(iv) iron(ii)sulphide calcium trioxocarbonate(iv) sodium tetraoxosulphate(vi) copper(ii)trioxocarbonate(iv) 35. Which of the following alloys contain Tin and Lead? solder bronze steel brass coinage metal 36. The rate of production of hydrogen gas from the reaction between zinc granules and hydrochloric acid can be increased by Carrying out the reaction at a higher pressure Using zinc rod instead of zinc granules Using zinc powder instead of granules Cooling the reaction mixture 37. Chemical equilibrium is attained when Reactants in the system are used up Concentration of the reactants is greater than that of the products Concentration of products is greater than that of the reactant Concentrations of the products and reactants remain constant 38. Which of these elements will not displace hydrogen from dilute hydrochloric acid? Magnesium Zinc Copper Potassium 39. What volume of propane is left unreacted when 20cm³ of oxygen reacts with 20cm³ of propane? 40cm³ 16cm³ 20cm³ 1cm³ 5cm³ 40. Fructose and glucose are isomers with a molecular formula C6H12O6. Which of these statements is true of both? fructose gives a brick red ppt with Fehlings solution but glucose does not glucose and fructose are non-reducing sugars both have an alkanal group fructose has an alkanone group while glucose has an alkanal group fructose has an alkanal group while glucose has an alkanone group 41. The formula of the fourth member of the carboxylic family is C3H7COOH C3H6COOH C4H9COOH C3H5COOH C4H7COOH 42. Which of the following substances decompose when an electric circuit is passed through it? glucose solution dilute hydrochloric acid tetra chloromethane zinc rod 43. Substance Q reacts with cold water to form a solution which turns red litmus blue?Substance Q could be Calcium Nitrogen Sulphur Phosphorus 44. The Azimuthal quantum number which corresponds to the f-orbital is 6 0 3 1 2 45. The gaseous product formed when ammonia is passed over heated copper(ii)oxide is Oxygen Hydrogen Nitrogen(ii)oxide Nitrogen Nitrogen(i)oxide 46. 15dm³ of a gas at s.t.p. in a tube was pressed by a piston whose pressure was increased to twice its original value at the same temperature. The volume of the gas in dm³ at this new pressure is 10.0dm³ 5.0dm³ 30.0dm³ 7.5dm³ 12.0dm³ 47. The bleaching of wood pulp for making paper by sulphur(iv)oxide is a process of oxidation vulcanization reduction refining desulphurisation 48. What is detergent? A liquid surfactant A liquid soluble A liquid solution A liquid sovent 49. Dilute HCl produces a gas with each of the following compounds EXCEPT sodium tetraoxosulphate(vi) sodium trioxosulphate(iv) copper(ii)trioxocarbonate(iv) calcium trioxocarbonate(iv) iron(ii)sulphide 50. A finely divided form of a metal burns more readily in air than the rod form because the rod has Smaller surface area Different chemical properties Higher molar mass Protective oxide coating 51. An element Y has the electronic configuration 1s2 2s2 2p6 3s2 3p4 How many shared pair of electrons are present in element Y? 7 4 5 6 52. A finely divided form of a metal burns more readily in air than the rod form because the rod has Protecting oxide coating Smaller surface area Different chemical properties Higher molar mass 53. Which of the following does NOT have the electronic structure of Argon? sulphide ion potassium ion aluminium ion chloride ion calcium ion 54. Radioisotopes can be used:I. As radioactive tracersII. for sterilizationIII. in photographyIV. for dyeing IV Only I, II and III Only I, II, III and IV III and IV Only I and II Only 55. Which of the following is not a separation technique? crystallization hydration evaporation filtration distillation 56. The gas given off when calcium is added to water is Oxygen Nitrogen(iv)oxide Hydrogen Calcium oxide 57. What is the composition of soap? Sodium and Potassium salt mixed with chemicals Potassium salt with fatty acids Both a & b Sodium salt with fatty acids. 58. Potassium Methanoate is a salt of a weak acid and a strong base. When it is added to water, it neutralizes itself hydrolyses to give a solution which turns blue litmus red hydrolyses to give a solution which turns red litmus blue does not dissolve dissolves to give a neutral solution 59. If the density of Hg at 273k is 13.5g/cm³. The volume occupied by 30g of Hg will be ............cm³ 0.45 2.22 1.22 2.18 3.00 60. Solid NH4Cl and KCl are mixed together. How could they be separated easily? Dissolution of the mixture in water followed by filtration Precipitation by the addition of AgNO3 solution to the mixture dissolved in water Extraction Decantation of an aqueous solution of the mixture Sublimation 1 out of 60 Time is Up! 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