23/04/2020Senior Class WAEC/NECO/UTME Mock Exams(Chemistry) 0Comments by Gate Academy Please, fill out the information below to continue. NAME EMAIL PHONE NUMBER 1. Which of the following is true of gamma (γ) rays? Theyare negatively chargedhave no ionizing powerare positively chargedtravel at very low speedare neutral2. The loss of molecules of water of crystallization to the atmosphere by some crystalline salt is known asDeliquescenceHygroscopyEfflorescenceEffervescence3. Which of the following is true of Ionisation energy?it increases across the periodit increases down the groupit is the energy due to electron gainthe higher the screening effect, the higher the ionization energyit is unaffected by nuclear charge4. The following salts can be prepared by a double decomposition reaction EXCEPTBaSO4PbCl2AgClBaCO3KCl5. 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 is30.0dm³7.5dm³10.0dm³5.0dm³12.0dm³6. Which of the following alloys contain Tin and Lead?brasscoinage metalsteelsolderbronze7. An element Y has the electronic configuration1s2 2s2 2p6 3s2 3p4 How many shared pair of electrons are present in element Y?47568. In which of the following compounds does sulphur have an oxidation number of +4H2SO4H2S207Na2SO3SO3H2S9. A synthetic rubber is having__________weight.Higher atomicHigher molecularHigher resistanceLower density10. When ammonium chloride is dissolved in water in a test tube, the test tube feels cooler showing that?The solution is unsaturatedSublimation has occurredAmmonia gas is evolvedThe process is endothermic11. The main constituents of petroleum aresolidsgasesalkyneshydrocarbonsalkanes12. Which acid is present in lemon?citric acidlactic acidtartaric acidmarlic acid13. What volume of distilled water would be added to 30cm³ of 18mol/dm³ HCl in order to dilute it 20 times? [ H=1, Cl=35.5, M.V=22400cm³]27cm³360cm³12cm³542cm³600cm³14. Chemistry is a branch of science which can be used for providing the services to mankind. Comment on the statement.May BeStrongly notTrueFalse15. Which of the following gives a yellow precipitate of a metallic derivative when reacted with ammoniacal silver trioxonitrate(v) at room temperature?propanepropyneethanolethanalbutene16. The formula of the fourth member of the carboxylic family isC4H7COOHC4H9COOHC3H7COOHC3H6COOHC3H5COOH17. Solid NH4Cl and KCl are mixed together. How could they be separated easily?Decantation of an aqueous solution of the mixtureDissolution of the mixture in water followed by filtrationExtractionSublimationPrecipitation by the addition of AgNO3 solution to the mixture dissolved in water18. Potassium Methanoate is a salt of a weak acid and a strong base. When it is added to water, ithydrolyses to give a solution which turns red litmus bluedissolves to give a neutral solutiondoes not dissolvehydrolyses to give a solution which turns blue litmus redneutralizes itself19. What property of hydrogen makes it suitable for filling balloons?Its tensile strengthIts low densityIts solubilityIts flammability20. The kinetic theory of gases can be used to explain all the following EXCEPTGay-Lussac's lawExpansion of gasesDiffusion of gasesDalton's atomic theoryGraham's law21. 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?QSRP22. What is the effect of using vanadium(v)oxide as catalyst in the reaction represented by the following equation?2SO2(g) + O2(g) ↔ 2SO3(g); ∆H = -xKj/molIncreases the collision rate of reactant particleShifts equilibrium position to the rightDecreases the value of ∆HReduces the time for the attainment of equilibrium23. When ammonium chloride is dissolved in water in a test tube, the test tube feels cooler showing that?Ammonia gas is evolvedSublimation has occurredThe process is endothermicThe solution is unsaturated24. CuSO4.5H2O can be obtained from an aqueous solution of copper(ii)tetraoxosulphate(vi) byPrecipitationEvaporation to drynessUsing chromatographyCrystallization25. H2(g) + I2(g) ↔ 2HI(g) In the reaction, increasing the pressure willdecrease the concentration of HIhave no effect on the equilibrium positionfavour the backward reactionincrease the concentration of HIfavour the forward reaction26. The natural sources of hydrocarbons are:I. CoalII. Natural gasIII. PetroleumIV. Organic compoundsI,II and III OnlyI and II OnlyIV OnlyIII and IV OnlyI, II, III and IV27. As a vegetable preservative poly______ foam is usedUthaneUrethanesUriathenesUrathanes28. The following metals are usually extracted by the method of electrolysis EXCEPTpotassiumaluminiummagnesiumironsodium29. 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 notglucose and fructose are non-reducing sugarsfructose has an alkanal group while glucose has an alkanone groupfructose has an alkanone group while glucose has an alkanal groupboth have an alkanal group30. An exothermic reaction is one which involvesEvolution of gas as it proceedsAttainment of dynamic equilibriumLoss of heat to the surroundingsPositive change in value of enthalpy31. If a metal R forms a compound with the formula R(NO3)2 , the formula of its tetraoxosulphate(vi) is?R(SO4)2R2(SO4)3RSO4R2SO432. Which of the following is not an isotope of hydrogen?DeuteriumProtiumProtonTritium33. Which of the following is NOT a halogen?bromineiodinefluorineastatinesilicon34. The Azimuthal quantum number which corresponds to the f-orbital is3016235. Dynamic equilibrium describes a situation where?Reactants are converted to productsBoth forward and reverse reactions proceed at the same rateReaction gives back the reactantA concentration of reactants and product is equal36. The rate of production of hydrogen gas from the reaction between zinc granules and hydrochloric acid can be increased byCooling the reaction mixtureCarrying out the reaction at a higher pressureUsing zinc powder instead of granulesUsing zinc rod instead of zinc granules37. When hydrogen sulphide gas is passed through an acidified solution of potassium heptaoxo dichromate(vi), the orange colour changes to green. This is because thechromium(vi) ion is oxidizedsulphide ion changes to sulphur atom+3 state of Cr is oxidized to +6 statehydrogen sulphide is a good oxidizing agent+6 state of Cr is reduced to +3 state38. Which of the following is not a type of elements?MetalsMetalloidsGasesNon Metals39. Which of the listed molecules has two lone pairs of electrons?watercarbon(iv)oxideammoniahydrogen gasbenzene40. Dilute HCl produces a gas with each of the following compounds EXCEPTiron(ii)sulphidecopper(ii)trioxocarbonate(iv)sodium tetraoxosulphate(vi)calcium trioxocarbonate(iv)sodium trioxosulphate(iv)41. N2O4(g) ↔ 2NO2(g)In the endothermic reaction above, more product formation will be favoured byA decrease in volumeDecreasing the temperatureIncrease in volumeAn increase in pressure42. A finely divided form of a metal burns more readily in air than the rod form because the rod hasProtective oxide coatingSmaller surface areaDifferent chemical propertiesHigher molar mass43. In the reaction belowMnO2 + 4HCl → MnCl2 + Cl2 + 2H2O Hydrochloric acid functions as a/anacidreducing agentprecipitating agentdehydrating agentoxidizing agent44. When ΔH is negative, the reaction is said to be,IonicEndothermicIrreversibleReversibleExothermic45. RDX is chemical compound. How is it used?As an nuclear weaponAs an reactorAs an explosiveAs an composition46. In which form is natural petroleum found?KeroseneGasolineCrude OilTar47. Example(s) of colloids include:I. emulsionsII. solsIII. FogIV. smokeIV OnlyI, II and III OnlyIII and IV OnlyI, II, III and IVI and II Only48. The Azimuthal quantum number which corresponds to the f-orbital is0623149. The gaseous product formed when ammonia is passed over heated copper(ii)oxide isNitrogenHydrogenNitrogen(i)oxideOxygenNitrogen(ii)oxide50. When excess ammonia is added to an aqueous copper(ii)tetraoxosulphate(vi), a deep blue solution of copper(ii)tetraamine is formed. The type of bond in copper(ii)tetraamine isionic bondvan der waalscoordinate covalent bondcovalent bondhydrogen bond51. Radioisotopes can be used:I. As radioactive tracersII. for sterilizationIII. in photographyIV. for dyeingI and II OnlyI, II and III OnlyI, II, III and IVIII and IV OnlyIV Only52. The catalyst generally used in the synthesis of methanol from carbon(ii)oxide and hydrogen iscopper-zinc oxidevanadium(v)oxideplatinumnickelzinc oxide53. Helium is preferred to hydrogen in filling balloons because hydrogen?is diatomicExhibits isotopyis inflammableis a component of water54. An element Y has the electronic configuration1s2 2s2 2p6 3s2 3p4 To what period does it belong in the periodic table?453655. Which of these is not a property of a system that is in a state of chemical equilibrium?The value of change in free energy is zeroThe change in entropy is zeroIt must take place in a closed systemIt is a reversible system56. An element Y has the electronic configuration1s2 2s2 2p6 3s2 3p4 How many lone pair of electrons are present in element Y?432157. Which of these elements will not displace hydrogen from dilute hydrochloric acid?ZincPotassiumMagnesiumCopper58. What current in amperes will deposit 2.7g of aluminium in 2 hours?[Al = 27, 1F = 96500C]1632828459. Which of the following alloys contain Tin and Lead?brasssoldercoinage metalsteelbronze60. Which is not used as an alkali?Potassium hydroxideCarbon hydroxideNitrogen hydroxideSodium hydroxide61 out of 60Time is Up!