Question 0X + Y = Z is an equilibrium reaction. The addition of a catalyst?A.increase the amount of Z produced in a given timeB.increases the rate of change in concentrations of X, Y and ZC.increases the rate of disapearance of X and YD.increases the rate of the forward reactionE.decreases the amounts of X and Y left after the attainment of equilibriumObjective Show full explanation
Question 0What is the formula of sodium gallate if gallium (Ga)shows an oxidation number of + 3?A.NaGaO3B.Na2Ga(OH)3C.NaGa(OH)3D.NaGa(OH)4E.NaGaOObjective Show full explanation
Question 0If the ONLY pollutants found in the atmosphere over a city are oxides of nitrogen, suspended lead compounds. carbon monoxide and high levels of methane, the probable source(s) of the pollution must be?A.automobile exhaust and biological decompositionB.combustion of coal and automobile exhaustC.biological decomposition onlyD.combustion of coal, automobile exhaust and biological decompositionE.combustion of coal and biological decompositionObjective Show full explanation
Question 0A correct electrochemical series can be obtained from K, Na, Ca, Al, Mg, Zn, Fe, Pb, H, Cu, Hg, Ag, Au by interchanging?A.Al and MgB.Zn and FeC.Zn and PbD.Pb and HE.Au and HgObjective Show full explanation
Question 0A certain industrial process is represented by the chemical equation 2A(g) + B(g) \(\to\) C(g) + 3D(g) \(\Delta\)H = X kJmol-1. Which of the following conditions will favour the yield of the products?A.increase in temperature, decrease in pressureB.increase in temperature, increase in pressureC.decrease in temperature,increase in pressureD.decrease in temperature, decrease in pressureE.constant in temperature, increase in pressureObjective Show full explanation
Question 02MnO-4 + 10Cl- + 16H+ → 2Mn2+ + 5Cl2 + 8H2O. Which of the substances serves as an oxidizing agent?A.Mn2+B.Cl-C.H2OD.MnO-4E.Cl2Objective Show full explanation
Question 0Which of the following metals will displace iron from a solution of iron(ll)tetraoxosulphate(lV)?A.CopperB.MercuryC.SilverD.ZincE.GoldObjective Show full explanation
Question 0In the reaction H2(g)O \(\to\) H2(g) + 1/2O2(g) ΔH = -2436000 KJ, which of the following has no effect on the equilibrium position?A.Adding argon to the systemB.Lowering the temperatureC.Adding hydrogen to the systemD.Decreasing the pressureE.Increasing the temperatureObjective Show full explanation
Question 0Complete hydrogenation of ethyne yields?A.benzeneB.methaneC.ethaneD.etheneE.propaneObjective Show full explanation
Question 0Which of the following is used in the manufacture of bleaching powder?A.Sulphur dioxideB.ChlorineC.Hydrogen tetraoxosulphate (VI)D.Hydrogen sulphideE.Nitrogen dioxideObjective Show full explanation
Question 0A man suspected of being drunk is made to pass his breath into acidified potassium dichlormate solution. If his breath carries a significant level of ethanol, the final colour of the solution is?A.pinkB.purpleC.orangeD.blue-blackE.greenObjective Show full explanation
Question 0When pollen grains are suspended in water and viewed through a microscope, they appear to be in a state of constant but erratic motion. This is due to?A.convection currentsB.small changesC.small changes in temperatureD.a chemical reaction between the pollen grain and waterE.the bombardment of the pollen grains by molecules of waterObjective Show full explanation
Question 0The energy change (ΔH) for the reaction CO(g) + (1)/(2)O2(g) → is? (ΔHi(CO) = -110.4 kJ mol-) (ΔHi(CO2) = -393 kJ mol-)A.-503.7 kJB.+503.7kJC.-282.9 kJD.+282.9 kJE.+393.3 kJObjective Show full explanation
Question 0Tetraoxosulphate (IV) ions are finally tested using?A.acidified silver nitrateB.acidified barium chlorideC.ime-waterD.dilute hydrochloric acidE.acidified lead nitrateObjective Show full explanation
Question 0An organic compound decolourized acidified KMnO4 solution but failed to react with ammoniacal silver nitrate solution. The organic compound is likely to be?A.a carbonxylic acidB.an alkaneC.an alkeneD.an alkyneE.an akanoneObjective Show full explanation
Question 0Solid sodium hydroxide on exposure to air absorbs a gas and ultimately gives another alkaline substance with the molecular formula?A.NaOH.H2OB.NaOH.N2C.Na2CO3OD.NaHCO3E.NaNO3OObjective Show full explanation
Question 0Which of the following substances is the most abundant in the universe?A.CarbonB.AirC.WaterD.OxygenE.HydrogenObjective Show full explanation
Question 0A colourless organic compound X was burnt in excess air to give two colourless and odourless gases, Y and Z, as products. X does not decolorize blue bromine vapour, Y turns lime milky while Z gives a blue colour with copper (ll) tetraoxosulphate (IV). Compound X is?A.an alkeneB.an alkaneC.an alkyneD.tetrachloromethaneE.dichloromethaneObjective Show full explanation
Question 0A colourless organic compound X was burnt in excess air to give two colourless and odourless gases, Y and Z, as products. X does not decolorize blue bromine vapour, Y turns lime milky while Z gives a blue colour with copper (ll) tetraoxosulphate (IV). Y and Z are respectively?A.CO2 and NH3B.CO and NH3C.SO2 and H2OD.CO2 and H2OE.SO2 and NH3Objective Show full explanation
Question 0Which of the following compounds is NOT the correct product formed when the parent metals is heated in air?A.Calcium oxide (CaO)B.Sodium oxide (Na2O)C.Copper (ll) oxide (CuO)D.Tri-iron tetroxide (Fe3O4)E.Aluminium oxide (Al2O3)Objective Show full explanation
Question 0The atomic number of an element whose cation, X2+, has the ground state electronic configuration 1s22s22p63s22p6 is?A.16B.18C.20D.22E.24Objective Show full explanation
Question 0When marble is heated to about 1473 K, another white solid is obtained which reacts vigorously with water to give an alkaline solution. The solution contains?A.NaOHB.KOHC.Mg(OH)2D.Zn(OH)2E.Ca(OH)2Objective Show full explanation
Question 0Addition of dilute hydrochloride acid to an aqueous solution of a crystalline salt yield a yellow precipitate and a gas which turned dichromate paper green. The crystalline salt was probably?A.Na2SO4B.Na2SC.Na2S2O3.5H2OD.Na2CO3E.NaHCO3Objective Show full explanation
Question 0The process involved in the conversion of an oil into margarine is known as?A.hydrogenationB.condensationC.pyrolysisD.dehydrationE.crackingObjective Show full explanation
Question 0An aqueous solution of an inorganic salt gave white precipitate (i) soluble in excess aqueous NaOH (ii) insoluble in excess aqueous NH3 (iii) with dilute HCl. The cation present in the inorganic salt is?A.Na4+B.Ca++C.Zn++D.Al+++E.Pb++Objective Show full explanation
Question 0Which of the following roles does sodium chloride play in soap preparation? ItA.reacts with glycerolB.purifies the soapC.accelerates the decomposition of the fat or oilD.separates the soap from the glycerolE.converts the fatty acid to its sodium saltObjective Show full explanation
Question 0The function of sulphur during vulcanization rubber is to?A.act as catalyst for the polymerization of rubber moleculesB.convert rubber from thermosetting to thermo plastics polymerC.from chains which bind rubber molecules togetherD.break down rubber polyerE.shorten the chain length of rubber polyerObjective Show full explanation
Question 0Figure 1 above shows part of the periodic Table which of the elements belongs to the p-block?A.S, T and UB.V, W and XC.S and T onlyD.P, Q and RE.V, W, X and SObjective Show full explanation
Question 0The diagram shown above represents the solubility curves of two salts, X and Y, in water, use this diagram to answer the question. At room temperature (300 K)A.Y is twice as soluble as XB.X is twice as soluble as YC.X and Y are soluble to the same extentD.X is three times as soluble as YE.Y is three times as soluble as XObjective Show full explanation
Question 0The diagram shown above represents the solubility curves of two salts, X and Y, in water, use this diagram to answer the question. If 80 g each of X and Y are taken up in 100 g of water at 353 K we shall haveA.only 10g of X undissolvedB.only 16 g of Y undissolvedC.10 g of X and 16 g of Y undissolvedD.all X and Y dissolvedE.all X and Y undissolvedObjective Show full explanation
Question 0The diagram shown above represents the solubility curves of two salts, X and Y, in water, use this diagram to answer the question. If the molar mass of X is 36 g, the number of moles of X dissolved at 343 K isA.0.2 molesB.0.7 molesC.1.5 molesD.2.0 molesE.3.0 molesObjective Show full explanation
Question 0Use the above options to the question. The products formed on hydrolysis ofA.AB.BC.CD.DE.EObjective Show full explanation
Question 0The oxidation ofA.2-butanoneB.2-butanalC.butaneD.butanoic acidE.3-butanalObjective Show full explanation
Question 0The I.U.P.A.C name for the compoundA.2-methyl-3-penteneB.4-methyl-2-pentaneC.2-methyl-2-penteneD.4-methylpent-2-eneE.2-methyl-3-pentaneObjective Show full explanation
Question 0Use the following option above to answer this question. Which of the following is the functional group of carboxylic acids?A.AB.BC.CD.DE.EObjective Show full explanation
Question 0Which of the following conduct electricity?A.sulfurB.graphiteC.diamondD.red phosphorusE.yellow phosphorusObjective Show full explanation
Question 0An organic compound contains 72% carbon, 12% hydrogen and 16% oxygen by mass. The empirical formula of the compound isA.C8H22O3B.C6H10O3C.C12H12OD.C6H12OE.C3H6OObjective Show full explanation
Question 00.499g 0f CuSO4.xH2O when heated to constant weight gave a residue of 0.346g. the value of x is? (Cu = 63.5, S = 32.0, O = 16, H = 1)A.0.5B.2.0C.3.0D.4.0E.5.0Objective Show full explanation
Question 0In the experiment, which of the following observations would suggest that a solid sample is a mixture? TheA.solid can be ground to a fine powderB.density of the solid is 2.25gdm-3C.solid begins to melt at 573k but is not completely melted until 648kD.solid absorbs moisture from the atmosphere and turns into liquidE.solid melts at 300kObjective Show full explanation
Question 0Hydrogen diffuses through a porous plugA.at the same rate as oxygenB.at a slower rate than oxygenC.twice as fast as oxygenD.three times as fast as oxygenE.four times as fast as oxygenObjective Show full explanation
Question 0Given that the molecular mass of iron is 56 and that of oxygen is 16, how many moles of iron(iii)oxide will be contained in 1kg of the compound?A.25.0 molesB.12.5 molessC.6.25 molesD.3.125 molesE.0.625 molesObjective Show full explanation
Question 03.0g of a mixture of potassium carbonate and potassium chloride were dissolved in a 25cm3 of this solution required required 40.00cm3 of 0.1M HCl for neutralization. What is the percentage by weight of K2CO3 in the mixture. (K = 39, O = 16, C = 12)A.60B.72C.82D.89E.92Objective Show full explanation
Question 0Some properties of chemical substances are mentioned below... i. sour taste ii. slippery touch iii. yields alkaline gas with ammonium salt iv. has pH less than 7 v. turns phenolphthalein pink. Which of the above are NOT typical properties of alkalis?A.i, iv and vB.iv and vC.i and ivD.ii and vE.ii, iii and ivObjective Show full explanation
Question 0A certain volume of gas at 298k is heated such that its volume and pressure are now four times the original values. What is the new temperature?A.18.6kB.100.0kC.298.0kD.1192.0kE.4768.0kObjective Show full explanation
Question 0Hydrogen is not liberated when trioxonitrate(v)acid reacts with zinc becauseA.zinx is not rendered passive by acidB.hydrogen produced is oxidized to waterC.oxides of nitrogen are producedD.all nitrates are soluble in waterE.trioxonitrate(v)acid is a strong acidObjective Show full explanation
Question 0The boiling point of water, ethanol, toluene and butan-2-ol are 373.0k, 351.3k, 383.6k and 372.5k respectively. Which liquid has the highest vapour pressure at 323.0k?A.waterB.tolueneC.ethanolD.butan-2-olE.noneObjective Show full explanation
Question 0In what respect will two dry samples of nitrogen gas differ from each other if sample 1 is prepared by completely removing CO2 and O2 from air, and sample 2 is prepared by passing purified nitrogen(i)oxide over heated copper? sample 1 isA.purer than sample 2B.slightly denser than sample 2C.in all respects the same as sample 2D.colourless but sample 2 has a light brown colourE.slightly less reactive than sample 2Objective Show full explanation
Question 0Copper sulphate solution is electolysed using platinum electrodes A. current of 0.193 amperes is passed for 2hrs. How many grams of copper are deposited? (cu = 63.5, F = 96500 coulombs)A.0.457gB.0.500gC.0.882gD.0.914gE.1.00gObjective Show full explanation