SS 3 CHEMISTRY PAST QUESTIONS (WAEC/NECO)HomeWAEC/NECO Exam Past QuestionsSS 3 CHEMISTRY PAST QUESTIONS (WAEC/NECO)0% SSCE/NECO/GCE (CHEMISTRY PAST QUESTIONS)CHEMISTRY PAST QUESTIONS APPQuestions will be picked at random from the question bank.You can use the NEXT button to move to the next question, use the PREV button to move to the previous question, the CLEAR button to clear any answer of your choice and you have the FINISH button to end the exam if you choose to.Any question not answered before the end of the exam time, will be marked as wrong and the exam will end by itself. so try to attempt all questions on time.Goodluck! 1 / 80 Category: CHEMISTRY PAST QUESTIONSWhat is the function of sulphur (IV) oxide in the reaction represented by the following equation? SO 2(aq) + 2H2S(g) → 3S (s) + 2H 2O (l) Bleaching agent Acid Dehydrating agent Oxidising agent 2 / 80 Category: CHEMISTRY PAST QUESTIONSIt can be concluded that gastric juice contains enzymes is a mixture is acidic has pH value of 7 3 / 80 Category: CHEMISTRY PAST QUESTIONSHelium is preferred to hydrogen in filling balloons because hydrogen is a component of water is inflammable is diatomic exhibits isotopy 4 / 80 Category: CHEMISTRY PAST QUESTIONSChemical equilibrium is attained when concentrations of the products are greater than those of the reactants concentrations of the reactants and products remain constant reactants stop forming the products reactants in the system are used up 5 / 80 Category: CHEMISTRY PAST QUESTIONSThe gas evolved when dilute tetraoxosulphate (VI) acid reacts with sodium hydrogen trioxocarbonate (IV) is sulphur (VI) oxide carbon (IV) oxide oxygen hydrogen 6 / 80 Category: CHEMISTRY PAST QUESTIONSA concentrated solution containing H+, Cu2+,OH- and CI- was electrolysed using platiunm electrodes which of the ions will be discharged at the cathods? Cu2+ OH- CI- H+ 7 / 80 Category: CHEMISTRY PAST QUESTIONSElements which belong to the same group in the Periodic Table are characterized by presence of the same number of outermost electrons in the respective atoms difference of +1 in the oxidation numbers of successive members presence of the same number of electron shells in the respective atoms difference of 14 atomic mass units between successive members 8 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following statements about ideal gases is/are correct?I. The cohesive forces between their particles are negligiblell. The have no definite volume but occupy the volume of their containersIII. They are not compressibleIV. Their particles collide with loss of energy l only l, ll and lll only l, ll, lll, and IV l and ll only 9 / 80 Category: CHEMISTRY PAST QUESTIONSA sheet of paper is placed in the path of a beam from a radioactive source. The emissions that pass through the paper consist of alpha particles and gamma rays beta particles and gamma rays alpha particles only alpha and beta particles 10 / 80 Category: CHEMISTRY PAST QUESTIONSGas molecules are said to be perfectly elastic because the volume occupied by them is negligible they collide without loss of energy they move about in straight lines the distances between them are negligible 11 / 80 Category: CHEMISTRY PAST QUESTIONSIf the solubility of KHCO3 is 0.40 mole dm-3 4.0g 40.0g 10.0g 100.0g 12 / 80 Category: CHEMISTRY PAST QUESTIONSAluminium is extracted from magnetite bauxite cassiterite cryolite 13 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following will displace copper from a solution of copper (ll) salt? Silver Zinc ions Magnesium Aluminium ions 14 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following compounds dissolves in water to give an alkaline solution? Ammonium chloride Sulphur (IV) oxide Potassium oxide Sodium chloride 15 / 80 Category: CHEMISTRY PAST QUESTIONSMetals are said to be malleable because they can be beaten into sheets are good conductors of electricity can be alloyed are good conductors heat 16 / 80 Category: CHEMISTRY PAST QUESTIONSA radioactive solid is best stored in a cool, dark cupboard under paraffin oil in a box lined with lead under ultraviolet light 17 / 80 Category: CHEMISTRY PAST QUESTIONSAn exothermic reaction is one which involves loss of heat to the surrounding attainment of dynamic equilibrium positive change in value of enthalpy evolution of gas as it proceeds 18 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following movements can be described as random motion? car travelling on a straight line planets going round the sun wheelbarrow being pushed gas molecules colliding in a flask 19 / 80 Category: CHEMISTRY PAST QUESTIONSThe spontaneity of a chemical reaction is determined by the change in the concentration of the reactants temperature of the system free energy of the system pressure applied to the system 20 / 80 Category: CHEMISTRY PAST QUESTIONSA finely divided from of a metal burns more readily in air than the rod from because the rod has smaller surface area higher molar mass protective oxide coating different chemical properties 21 / 80 Category: CHEMISTRY PAST QUESTIONSIf an element with high electron affinity combines with another element with low ionization energy the bond formed will be mainly covalent ionic dative metallic 22 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following increases as boiling water changes to steam? temperature of the system number of molecules activation energy degree of disorder in the system 23 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following features of a human skeleton can be determined by carbon-dating? Height Mass Race Age 24 / 80 Category: CHEMISTRY PAST QUESTIONSWhat does ∆H represent in the following equation ? Cl(g) + e- → CI- (g); ∆H = - 363 kJ mol-1 Dissociation energy Electron affinity lonization energy Heat of atomization 25 / 80 Category: CHEMISTRY PAST QUESTIONSWhat is the value of x in the following equation? Cr2O72- + 14H+ + xe- → 2Cr3+ + 7H2O 12 6 8 1 26 / 80 Category: CHEMISTRY PAST QUESTIONSConsider the reaction represented by the following equation: H2(g) + 12(g) → 2HI(g). The number of effective collisions of molecules of the reactants decreases as the temperature is raised the volume of the system is increased a catalysty is intoduced into the system the pressure increased 27 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following contains co-ordinate covalent bond? HCI Na+CI CH4 NH4 28 / 80 Category: CHEMISTRY PAST QUESTIONSWhat will be the effect of increase in pressure on the following system at equilibrium? 2NH2(g) N2(g) + 3H2(g) the concentration of ammonia will increase Activation energy will decrease the forward reaction will be favoured the reaction will go to completion 29 / 80 Category: CHEMISTRY PAST QUESTIONSTwo radioactive elements Q and S have half-life periods of 10 hours and 20 hours respectively. Therefore Q is twice as stable as S S is more stable than Q S decays faster than Q Q emits fewer particles than S 30 / 80 Category: CHEMISTRY PAST QUESTIONSThe property of calcium chloride which makes it useful as a drying agent is that it is deliquescent ionic a strong electrolyte a normal salt 31 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following non-metals reacts most readily with metals? Chlorine Carbon Nitrogen Sulphur 32 / 80 Category: CHEMISTRY PAST QUESTIONSPetrol consists mainly of hydrocarbons alkanoates polymers alktanols 33 / 80 Category: CHEMISTRY PAST QUESTIONSWhat is the shape of a molecule of CCI4? Pyramidal Linear Tetrahedral Trigonal planar 34 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following is not correct about oxidation number convention? The oxidation number of a/an alkali meta like sodium in its compounds is + 1 atom of a diatomic molecules is + 2 monatomic ion is equal to its charge element in the free state is zero 35 / 80 Category: CHEMISTRY PAST QUESTIONSThe type of chemical bond that exists between potassium and oxygen in potassium oxide is dative covalent ionic metallic 36 / 80 Category: CHEMISTRY PAST QUESTIONSThe crystal layers in graphite are held together by van der Waals' forces covalent bonds electrostatic forces hydrogen bonds 37 / 80 Category: CHEMISTRY PAST QUESTIONSWhat type of reaction is involved when wood shavings produce a brown gas with concentrated HNO3? Destructive distillation Redox reaction Nutralization Dehydration 38 / 80 Category: CHEMISTRY PAST QUESTIONSChlorine atom forms CI by Losing one electron Sharing one electron Donating lone pair of electrons Gaining one electron 39 / 80 Category: CHEMISTRY PAST QUESTIONSCalcium atom ionizes by gaining two protons losing two electrons gaining two electrons sharing two electrons 40 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following will produce oxygen and hydrogen during its electrolysis using platinum electrode? Aqueous copper (ll) tetraoxosulphate (IV) Concentrated hydrochloric acid Dilute sodium chloride solution Glucose solution 41 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following properties increases down a group in the Periodic Table? Electronegativity Ionization energy Atomic radius Electon affinity 42 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following substances decomposes when an electric current is passed through it? Glucose solution Hydrochloric acid Tetrachlormethane Zinc rod 43 / 80 Category: CHEMISTRY PAST QUESTIONSWhat is responsible for metallic bonding? Attraction between the atomic unclei and cloud of electrons Sharing of electrons between the metal atoms Attraction between positive and negative ions transfer of electrons from one atom to another 44 / 80 Category: CHEMISTRY PAST QUESTIONSConsider the following equation: Ag+ (aq) + CI-(aq) → Ag+CI- (s) ; ∆H = _65.7 kJmol-1. From the equation, it can be deduced that activation energy is high and a catalyst is required the reaction is endothermic and occurs at high temperature a solid is formed and heat is evolved direct combination is involved and the reaction is endothermic 45 / 80 Category: CHEMISTRY PAST QUESTIONSA reaction is represented by the equation below. A2(g) + B2(g) 2AB(g); ∆H = +X kJmol-1 Which of the following statements about the system is correct? At equilibrium increase in temperature favours the reverse reaction Pressure has no effect on the equilibrium mixture The reaction goes to completion at equilibrium The forward reaction is exthermic 46 / 80 Category: CHEMISTRY PAST QUESTIONSThe atoms of four elements are represented as 20Q, 16R, 10S and 8T Which of the elements would be unreactive? S Q T R 47 / 80 Category: CHEMISTRY PAST QUESTIONSElectrovalent compounds are characterized by high molar mass solubility in ethanol high melting point strong oxidizing ability 48 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following compounds dissolves in water to form a solution with pH below 7? Sodium tetraoxosulphate (VI) Sodium trioxocarbonate (IV) Ammonium chloride Potassium hydroxide 49 / 80 Category: CHEMISTRY PAST QUESTIONSEqual volumes of CO2 cnd CO at s.t.p have the same number of molecules density rate of diffusion mass 50 / 80 Category: CHEMISTRY PAST QUESTIONS0.10 mol dm-3 NaCI conducts electricity better than 0.10 mol dm-3 CH3COOH because the solution of NaCI contains more ions has a higher pH is neutral to litmus has a lower molar mass 51 / 80 Category: CHEMISTRY PAST QUESTIONSPipe-borne water is usually chlorinated in order to coagulate sediments in the water remove the hardness in the water clear kill harmful bacteria in the water improve the teste of the water 52 / 80 Category: CHEMISTRY PAST QUESTIONS30cm3 pf hydrogen at s.t.p combine with 20cm3 of oxygen to form steam according to the following equation 2H2(g) + O2(g) → 2H2O(g). Calculate the total volume of the gaseous mixture at the end of the reaction 35cm cube 50cm cube 30cm cube 25cm cube 53 / 80 Category: CHEMISTRY PAST QUESTIONSA mixture of calcium chloride and calcium trioxocarbonate (IV) in water can be separated by filtration evaporation distillation sublimation 54 / 80 Category: CHEMISTRY PAST QUESTIONSWhat is oxidized in the reaction represented by the following equation? 3CU + 8HNO3 → 3Cu(NO3)2 + 2NO + 4H2O Oxygen Nitrogen Copper Hydrogen 55 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following procedures is suitable for identifying the food colouring added to a pastry sample? The cathode becomes coated with copper Both electrodes gain electrons The blue colour of the solution fades gradually The anode increases in mass 56 / 80 Category: CHEMISTRY PAST QUESTIONSOne mole of a compound M(HCO3)2 has a mass of 162g. Calculate the relative atomic mass of M. [H = 1, C =12, O = 16] 53 40 101 122 57 / 80 Category: CHEMISTRY PAST QUESTIONSWhat is the oxidation number of nitrogen in AI(NO3)3? + 6 + 5 + 3 + 1 58 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following occurs when a solution of CuSO4 is electrolysed using copper electrodes? Both electrodes gain electrons The blue colour of the solution fades gradually The anode increases in mass The cathode becomes coated with copper 59 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following lowers the activation energy of a chemical reaction? Reducing agent Water Catalyst Freezing mixture 60 / 80 Category: CHEMISTRY PAST QUESTIONSP Total = F1 + P2 + P 3 + .........Pn' where P Total is the pressure of a mixture of gasses. The equation above is an expression of Dalton's law Boyle's law Graham's law Gay-Lussac's Law 61 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following would dissolve in warm dilute H2SO4 without effervescence, to give a blue solution? Copper (ll) oxide Copper alloy Copper (ll) trioxocarbonate (IV) Copper turnings 62 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following pairs of reagents recat to produce hydrogen? Magnesium and dilute tetraoxosulphate (VI) acid Water and calcium dicarbide Copper and dilute hydrochloric acid Zinc and concentrated trioxonitrate (V) acid 63 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following can undergo both addition reactions and substitution reactions? Propene Hexane Pentane Benzene 64 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the orbitals 4s, 4p, 4d and 4f has the lowest energy? 4s 4p 4d 4f 65 / 80 Category: CHEMISTRY PAST QUESTIONSDehydration of ethanol produces ethanoic acid ethene propan-1,2,3-triol ethanal 66 / 80 Category: CHEMISTRY PAST QUESTIONSThe liquid product of the destructive distillation of coal is kerosene ammoniacal liquor paraffin oil ethanol 67 / 80 Category: CHEMISTRY PAST QUESTIONSThe presence of unpaired electrons in an atom of a transition metal gives rise to ductility nalleability shiny appearance paramagnetism 68 / 80 Category: CHEMISTRY PAST QUESTIONSIn the Periodic Table, the elements that loss electrons most readily belong to Group 111 A Group 1 A Group V11 A Group 11 A 69 / 80 Category: CHEMISTRY PAST QUESTIONSWhat mass of copper would be deposited by a current of 1. 0 ampere passing for 965 seconds through copper (ll) tetraoxosulphate (IV) solution? [Cu = 63.5; 1F = 96500C] 0.635g 0.318g 18g 6.35g 70 / 80 Category: CHEMISTRY PAST QUESTIONSSubstances which absorb water from the atmosphere without dissolving in it are said to be anhydrous hygroscopic hydrated insolube 71 / 80 Category: CHEMISTRY PAST QUESTIONSExhaust fumes discharged from a smoky vehicle gradually become invisible as a result of combustion absorption diffusion emission 72 / 80 Category: CHEMISTRY PAST QUESTIONSGiven that the order of reactivity of four metals is P>Q>R>S, which of the following reactions is feasible? S + Q+ → Q + S+ R + P+ → P + R+ Q + S+ → S + Q+ S + P+ → P + S + 73 / 80 Category: CHEMISTRY PAST QUESTIONSHow many electrons are removed from Cr2- when it is oxidized to CrO42-? 2 8 4 0 74 / 80 Category: CHEMISTRY PAST QUESTIONSWhat is the effect of using vanadium (V) oxide as catalyst in the reaction represented by the following equation? 2SO2 + O2 ⇌ 2SO3; ∆H = - xKJmol-1 Increases the collision rate of reactant particles Reduces the time for attainment of equilibrium Decreases the value of ∆H Shifts equilibrium position to the right 75 / 80 Category: CHEMISTRY PAST QUESTIONSElactrostatic force of attraction between sodium ion and halide ion is greatest in NaCI NaI NaF NaBr 76 / 80 Category: CHEMISTRY PAST QUESTIONSWhen alkanols react with sodium, the ga evolved is methane oxygen hydrogen ethyne 77 / 80 Category: CHEMISTRY PAST QUESTIONSRusting of iron is an example of decomposition deliquescence displacement reaction redox reaction 78 / 80 Category: CHEMISTRY PAST QUESTIONSWhich of the following methods is suitable for the preparation of an insoluble salt? Action of an acid on a trioxocarbonate (IV) Neutralisation Double decomposition Action of an acid on a metal 79 / 80 Category: CHEMISTRY PAST QUESTIONSWhat volume of hydrogen is produced at s.t.p. When 2.60 g of zinc reacts with excess HCI according to the following equation? Zn(s) + 2HCI(aq) → ZnCI 2(aq) + H2(g) [Zn = 65; 1 mole of a gas occupies 22.4dm3 at s.t.p] 5.82dm 3 0.040dm 3 8.62dm 3 0.896dm 3 80 / 80 Category: CHEMISTRY PAST QUESTIONSPauli Exclusion Principle is related to quantum numbers of electrons electronegativity values of elements reversiblility of equlibrium reactions collision theory of reaction rates Your score is 0% Restart quiz Practice also:SS 3 BIOLOGY PAST QUESTIONS (WAEC/NECO)SS 3 AGRIC SCIENCE PAST QUESTIONS (WAEC/NECO)SS 3 COMPUTER STUDIES PAST QUESTIONS (WAEC/NECO) SS 3 COMMERCE PAST QUESTIONS (WAEC/NECO)SS 3 DATA PROCESSING PAST QUESTIONS (WAEC/NECO)
