Question 0An acid is said to be weak if?A.its ions are so completely dissociated that they easily drift apartB.the acid is not corrosiveC.the acid has low specific gravityD.its ions move very slowly when in solutionE.its ions are incompletely dissociatedObjective Show full explanation
Question 0Which of the following statements is correct during the electrolysis of a caustic soda solution using platinum electrodes?A.Oxygen gas is given off at the cathodeB.Hydrogen gas is given of at the anodeC.Sodium metals is deposited at the anodeD.Sodium metal is deposited at the cathodeE.AAlkalinity at the cathode increasesObjective Show full explanation
Question 0An amphoteric oxide is an?A.amorphous oxide of a metalB.amorphous oxide of a non-mentalC.oxide that is insoluble in waterD.oxide that behaves both as a base as well as an acidE.oxide that loses its oxygen on sublimationObjective Show full explanation
Question 0Water is poured over a white solid and a colourless neutral gas is evolved which burns with a sooty flame. The white solid is?A.calciumB.calcium oxideC.calcium carbideD.sodium peroxideE.sodium sulphateObjective Show full explanation
Question 0Cotton is almost pure?A.starchB.proteinC.animal fibreD.celluoseE.mineral fibreObjective Show full explanation
Question 0Which of the following types of reactions takes place between C2H4 and the halogens?A.SubstitutionB.PolymerizationC.AdditionD.SaponificationE.OxidationObjective Show full explanation
Question 0The product formed at the the cathode during the electrolysis of sodium chloride solution with carbon electrodes is?A.sodiumB.chlorineC.hydrogenD.sodium hydroxideE.oxygenObjective Show full explanation
Question 0Sodium carbonate crystals on exposure to a dry atmosphere change to a white powder. This phenomenon is known as?A.deliquescenceB.hygroscopyC.oxidationD.efforescenceE.sublimationObjective Show full explanation
Question 0Which of the following statements is incorrect?A.Calcium reacts with water to form calciumB.Magnesium reacts very slowly with water but faster with warm waterC.Iron will not react with water in the absence of airD.Sodium reacts with waterE.Copper reacts with steamObjective Show full explanation
Question 0In the reaction NH3 + H+ → NH4+, the bond formed results from?A.an electron transferred from NH3 + H+B.an electron pair donated by NH3C.an electron pair equally sharedD.an electron pair donated by H+E.an electron tarnsferred from H+ to NH3Objective Show full explanation
Question 0Which of the following CANNOT be obtained by fractional distillation of petroleum?A.EtherB.MethaneC.ButaneD.EtheneE.HydrogenObjective Show full explanation
Question 0In the reaction N2(g) + O(g) ↔ 2NO(g) produced i an increase in the total pressure will?A.cause less nitrogen to be produced in the equilibrium mixtureB.cause less nitric oxide to be produced in the equilibrium mixtureC.cause more nitric oxide to be produced in the equilibrium mixtureD.cause more oxygen to be produced in the equilibrium mixtureE.have no effectObjective Show full explanation
Question 0In the chemical reaction A + B \(\to\) C + D, more of D is formed?A.if the concentrated of A is reducedB.if the concentrated of B is reducedC.if the concentrated of C is reducedD.if the concentration of C is increasedE.if D is continuously removed from the reaction mixtureObjective Show full explanation
Question 01.00 g of the oxide of metal X (atomic mass = 64) gave 0.80 g of the metal when reduced with hydrogen. The formula of the oxide is?A.X2OB.XOC.XO2D.X2O3E.X3O4Objective Show full explanation
Question 0When a solution of silver (l) nitrate is saturated with hydrogen sulphide, a black precipitate forms which is?A.H2SB.Ag2SC.PbSD.HNO3E.SObjective Show full explanation
Question 0The production of ammonia by the haber process may be represented by the equilibrium equation N2(g) + 3H2(g) ↔ 2NH3 ∆H = -22KJ. Therefore the production of ammonia will be favoured by?A.only high pressureB.only high temperatureC.a combination of high temperature and low pressureD.a combination of low temperature and high pressureE.low pressureObjective Show full explanation
Question 0Which of the following represents ethyl ethanonate?A.CH3CH2CO2CH3B.(CH3CO2)2OC.CH3CH2CO2CH2CH3D.CH3CO2CH2CH3E.CH3CH2COCH2CH3Objective Show full explanation
Question 0Which of the following equations represents an oxidizing action of sulphur dioxide?A.SO2 + 2HNO2 → H2SO4 + 2NO2 + heatB.2SO2 + 2H2O + O2 → 2H2SO4C.SO2 + 2H2O + CI2 → H2SO4 + 2HCID.SO2 + 2H2S → 3S + 2H2OE.K2Cr2O7 + H2SO4 + 3SO2 → K2SO4 + Cr2(SO4)3 + H2OObjective Show full explanation
Question 0If the rate of diffusion of oxygen gas is taken as 1, what will be rated of diffusion of methane whose relative molar mass is 16?A.2.0B.1.8C.1.4D.1.0E.0.5Objective Show full explanation
Question 0If the temperature of a gas is increased?A.the kinetic energy of the emolecules will decreaseB.the pressure will decrease if the volume is constantC.the gas will occupy a greater volume if the pressure is constantD.the mass of the gas will decreaseE.the pressure and volume will increaseObjective Show full explanation
Question 0When a little brine was added to a metal nitrate a white precipitate was formed which first turned violet and then black on exposure to ai. The metal nitrate is therefore?A.sodium nitrateB.mercuric nitrateC.lithium nitrateD.silver nitrateE.potassium nitrateObjective Show full explanation
Question 0If atom X with six electrons in its outermost shell combines with atom Y with one electron in its outermost shell to form an ionic compound, then?A.six atoms of X will combine with one of YB.two atoms of X will combine with six of YC.one atom of X will combine with two of YD.two atoms of X will combine with one of YE.one atom of X will combine with six of YObjective Show full explanation
Question 0The nitrogen gas obtained by burning an excess of phosphorus in air has a density higher than the nitrogen from nitrogen compounds because the nitrogen from air is contaminated with?A.some unburnt phosporusB.P2O5 vapourC.some oxygenD.rare gasesE.carbondioxideObjective Show full explanation
Question 0When air is passed through alkaline pyrogallol and then over quicklime, the only gases left are?A.nitrogen and carbondoxideB.the rare gasesC.nitrogen and oxygenD.nitrogen and the rare gasesE.nitrogen, carbonioxide and the rare gasesObjective Show full explanation
Question 09.8g of solid potassium chlorate (KCIO3) were added to 40 cm3 of water and heated to dissolve all the solid. As he solution cooled, crystals of potassium chlorate started forming at 60°C. The solubility of potassium chlorate at 66°C is therefore?A.24.5 mole per dm3B.0.2 mole per dm3C.10.0 mole per dm3D.20.0 mole per dm3E.2.0 mole per dm3Objective Show full explanation
Question 0100 cm3 of oxygen is made to react with 50 cm 3 of hydrogen, and the whole reaction mixture was then passed through anhydrous calcium chloride. What is the volume of gas left?A.5 cm3B.25 cm3C.50 cm3D.75 cm3E.100 cm3Objective Show full explanation
Question 0A mixture contains 20cm3 of hydrogen, 35cm3 of oxygen, 15cm3 of carbon monoxide and 10cm3 of nitrogen at S.T.P. Which of the following gives the mole fraction of hydrogen in this mixture?A.0.02B.0.16C.0.20D.0.25E.20Objective Show full explanation
Question 00.07g of a hydride of carbon occupies 56.0cm3 at S.T.P. when vaporized and contains 14.29% by mass of hydrocarbon is(C = 12, H = 1)A.CH4B.C2H2C.C2H4D.C2H6E.C3H8Objective Show full explanation
Question 0The pressure on 100 cm3 of oxygen gas at 35°C is 750mm of Hg.What would be the volume of the gas if the pressure is increased to 1000mm of Hg without changing the temperature?A.133.3 cm3B.85 cm3C.75 cm3D.65 cm3E.58.3 cm3Objective Show full explanation
Question 0Which of the following bonds exist in crystalline ammonium chloride (NH4Cl)?A.Ionic and covalentB.Ionic and co-ordinateC.Ionic covalent and co-ordinateD.Covalent , co-ordinate and metalllicE.Ionic, covalent and metallicObjective Show full explanation
Question 0When a pressure cooker is half filled with water, and heated to boiling point, then the pressure inside the cooker will?A.decrease, since only a fraction of the water molecules has changed to vapourB.remain constant, because the total number of water molecules has not changedC.increase, because the water molecules can now reach every part of the sealed tubeD.decrease, since water boils under reduced pressureE.increase, because the water vapour molecules now strike the walls of the tube more frequently because of their increased velocityObjective Show full explanation
Question 0An element X has two isotopes, 2010X and 2010X, present in the ratio 1:3. The relative atomic mass of X would be?A.20.5B.21.0C.21.5D.22.0E.22.5Objective Show full explanation
Question 0Which of the following is a neutralization reaction? Addition ofA.nitric acid to hydrochloric acidB.nitric acid to sulphuric acidC.nitric acid to distilled waterD.nitric acid to sodium hydroxideE.sodium chloride to distilled waterObjective Show full explanation
Question 0A current of 10.0A was passed for 1 hour through a solution of copper (ll) sulphate between the copper electrodes. Which of the following observation would be correct? (1 Faraday = 96,500 coulobms) (i) 0.186 mole of copper is dissolved from the anode. (ii) 0.372 mole of copper is deposited on the cathode. (iii) the original Cu2+ ion concentration of the solution remains unchanged. (iv) the original Cu2+ ion concentration of the solution decreases.A.i and iiB.i and iiiC.i and ivD.ii and iiiE.ii and ivObjective Show full explanation
Question 0In the preparation of carbon monoxide by heating ethanedioic acid with concentrated sulphuric acid, the concentrated sulphuric acid act as?A.an oxidizing agentB.a reducing agentC.a dehydrating agentD.a reaction mediumE.a catalystObjective Show full explanation
Question 0When copper powder is heated with concentrated sulphuric acid, the gas produced is?A.hydrogen sulphideB.sulphur dioxideC.sulphur trioxideD.hydrogen pentasulphideE.sulphur pentoxideObjective Show full explanation
Question 0Magnesium ribbon was added to each of the following aqueous solution in turn: H2SO4, AgNO3, HNO3, HCl, NH3, HCl, NH3. In which case does the magnesium become covered with a dark precipitate?A.H2SO4B.AgNO3C.HNO3D.NH3E.HClObjective Show full explanation
Question 0How many grams of methylacetylene (propyne) CH3 — C Ξ CH will completely discharge the colour of 8g of bromine? (Br = 80, C = 12, H = 1)A.0.5B.1.0C.2.0D.3.0E.4.0Objective Show full explanation
Question 0What weight of sodium hydroxide is required to make 500 cm3 of 0.2 M solution? (Na = 23, O = 16, H = 1)A.40 gB.20 gC.10 gD.4 gE.2 gObjective Show full explanation
Question 0Which of the following combinations of conditions may increase the rate of a chemical reaction?A.Decrease in temperature, increase in concentration of the reactantsB.Increase in temperature, addition of a catalyst, decrease in the surface area of the reactantsC.Increase in temperature, increase in concentration, addition of a catalyst and increase in the surface area of the reactantsD.Decrease in temperature concentration and surface area of the reactantsE.Additionof a catalyst and in the absence of lightObjective Show full explanation
Question 0Which of the following is NOT a redox reaction?A.2HNO2 + 2HI → 2H2O + 2NO + I2B.Zn + H2SO4 → ZnSO4 + H2C.Ca(HCO3)2 → CaCO3 + H2O + CO2D.4FeO + O2 → 2Fe2O3E.2Na + Cl2 → 2NaClObjective Show full explanation
Question 00.16g of methane when burnt raises the temperature of 100g of water by 40°C. What is the of combustion of methane when if the heat capacity of water is 4.2 Jg-1°C-1? (CH4 = 16)A.1,160 kJ mol-1B.1,180 kJ mol-1C.1,560 kJ mol-1D.1,600kJ mol-1E.1,680 kJ mol-1Objective Show full explanation
Question 0Which of the following processes NOT lead to a chemical change?A.Strirring iron in sulphur (IV) acidB.Stirring sodium carbonate in waterC.Stirring glucose in concentrated sulphur (IV) acidD.Mixing sulphur (IV) acid with potassium carbonateE.Titrating an acid against baseObjective Show full explanation
Question 0Brass is an alloy containing copper and?A.zincB.tinC.aluminiumD.silverE.leadObjective Show full explanation
Question 0The number of grammes of potassium hydroxide in 250cm3 of one molar solution is? (K = 39, O = 16, H = 1)A.40gB.52gC.100gD.26gE.14gObjective Show full explanation
Question 060cm3 of hydrogen are sparked with 20cm3 of oxygen at 100°C and 1 atmosphere. The total volume of the residual gases is?A.60 cm3B.10 cm3C.40 cm3D.30 cm3E.70 cm3Objective Show full explanation
Question 0The solubility curve of a solid X (molecular mass = 160) is as show above 1,000 cm3 of a saturated solution of X at 80oC . The weight of X crystalized out would beA.10 gB.12 gC.14 gD.16 gE.18 gObjective Show full explanation
Question 0The i.u.p.A.C name for the compoundA.2-chloro-isopentaneB.3-chloro-isopentaneC.2-chloro-2-methylbutaneD.1-chloro-2,2- dimethylpropaneE.2-chloro-2-ethylpropaneObjective Show full explanation
Question 01.00g of mixture of calcium carbonate and calcium oxide liberated 0.33g of carbon dioxide on strong heating. The percentage of calcium oxide in the mixture is? (Ca = 40, C = 12, O = 16)A.5B.15C.25D.35E.50Objective Show full explanation