2013 JAMB CHEMISTRY PAST QUESTIONS AND ANSWERS Leave a Comment / Jamb Chemistry / By Jamb Tutor Report a question What’s wrong with this question? You cannot submit an empty report. Please add some details. 0% 0 votes, 0 avg Created by Jamb TutorJamb Chemistry 2013 JAMB CHEMISTRY PAST QUESTIONS AND ANSWERS 1 / 43 Category: Jamb Chemistry 2013 1. $$\text{Which Question Paper Type of Chemistry is given to you?}$$ a) $$\text{Type D}$$ b) $$\text{Type I}$$ c) $$\text{Type B}$$ d) $$\text{Type U}$$ $$\text{Paper type ensures unique identification for exam monitoring.}$$ 2 / 43 Category: Jamb Chemistry 2013 2. $$\text{The presence of an impurity in a substance will cause the melting point to}$$ a) $$\text{Be zero}$$ b) $$\text{Reduce}$$ c) $$\text{Increase}$$ d) $$\text{Be stable}$$ $$\text{Impurities lower melting points by disrupting crystal structures.}$$ 3 / 43 Category: Jamb Chemistry 2013 3. $$\text{What volume of carbon (II) oxide is produced by reacting excess carbon with 10 dm}^3 \text{of oxygen?}$$ a) $$5 \text{ dm}^3$$ b) $$20 \text{ dm}^3$$ c) $$15 \text{ dm}^3$$ d) $$10 \text{ dm}^3$$ $$\text{Reaction: C + O}_2 \rightarrow \text{CO}_2. \text{Only 5 dm}^3 \text{O}_2 reacts.}$$ 4 / 43 Category: Jamb Chemistry 2013 4. $$\text{The rate of diffusion of a gas Y is twice that of Z. If } \text{RMM of Y is } 64, \text{ find RMM of Z.}$$ a) $$32$$ b) $$4$$ c) $$8$$ d) $$16$$ $$\text{Rate is inversely proportional to } \sqrt{\text{RMM}}. \text{ RMM}_Z = 16.}$$ 5 / 43 Category: Jamb Chemistry 2013 5. $$\text{The radioisotope used in industrial radiography to check weld faults is}$$ a) $$\text{Carbon-14}$$ b) $$\text{Phosphorus-32}$$ c) $$\text{Cobalt-60}$$ d) $$\text{Iodine-131}$$ $$\text{Cobalt-60 is widely used for industrial radiographic imaging.}$$ 6 / 43 Category: Jamb Chemistry 2013 6. $$\text{How many unpaired electrons are in the p-orbitals of a fluorine atom?}$$ a) $$3$$ b) $$0$$ c) $$1$$ d) $$2$$ $$\text{Fluorine has one unpaired electron in its p-orbital configuration (2p5).}$$ 7 / 43 Category: Jamb Chemistry 2013 7. $$\text{The radioactive emission with the least ionization power is}$$ a) $$\alpha\text{-particles}$$ b) $$\text{X-rays}$$ c) $$\gamma\text{-rays}$$ d) $$\beta\text{-particles}$$ $$\gamma\text{-rays have high penetration but low ionizing power.}$$ 8 / 43 Category: Jamb Chemistry 2013 8. $$\text{The shape of the carbon (IV) oxide molecule is}$$ a) $$\text{Linear}$$ b) $$\text{Angular}$$ c) $$\text{Tetrahedral}$$ d) $$\text{Pyramidal}$$ $$\text{CO}_2 \text{ is linear due to its sp hybridization and double bonds.}$$ 9 / 43 Category: Jamb Chemistry 2013 9. $$\text{Which of the following molecules is held together by hydrogen bond?}$$ a) $$\text{CH}_4$$ b) $$\text{HBr}$$ c) $$\text{H}_2\text{SO}_4$$ d) $$\text{HF}$$ $$\text{HF forms strong hydrogen bonds due to high electronegativity of F.}$$ 10 / 43 Category: Jamb Chemistry 2013 10. $$\text{The bond formed between two elements with configurations 1s}^2 2s^2 2p^6 3s^2 \text{ and 1s}^2 2s^2 2p^4 \text{ is}$$ a) $$\text{Metallic}$$ b) $$\text{Covalent}$$ c) $$\text{Dative}$$ d) $$\text{Ionic}$$ $$\text{Ionic bond forms between metal and non-metal by electron transfer.}$$ 11 / 43 Category: Jamb Chemistry 2013 11. $$\text{The constituent of air that acts as a diluent is}$$ a) $$\text{Nitrogen}$$ b) $$\text{Carbon (IV) oxide}$$ c) $$\text{Noble gases}$$ d) $$\text{Oxygen}$$ $$\text{Nitrogen makes up 78% of air and reduces the reactivity of oxygen.}$$ 12 / 43 Category: Jamb Chemistry 2013 12. $$\text{Steam changes the colour of anhydrous cobalt (II) chloride from}$$ a) $$\text{White to red}$$ b) $$\text{Blue to white}$$ c) $$\text{Blue to pink}$$ d) $$\text{White to blue}$$ $$\text{Anhydrous CoCl}_2 \text{ turns pink in the presence of water.}$$ 13 / 43 Category: Jamb Chemistry 2013 13. $$\text{An example of a hygroscopic substance is}$$ a) $$\text{CuO (s)}$$ b) $$\text{MgCl}_2 (s)$$ c) $$\text{CaCl}_2 (s)$$ d) $$\text{NaOH (s)}$$ $$\text{CaCl}_2 \text{ absorbs moisture from air but does not dissolve in it.}$$ 14 / 43 Category: Jamb Chemistry 2013 14. $$\text{If 24.4 g of lead (II) trioxonitrate (V) were dissolved in 42 g of distilled water at 20^{\circ}\text{C}, calculate the solubility of the solute in gdm}^{-3}. $$ a) $$581.000$$ b) $$0.581$$ c) $$5.810$$ d) $$58.100$$ $$\text{Solubility } = \frac{24.4}{42 + 24.4} \times 1000 \approx 581 \text{ gdm}^{-3}. $$ 15 / 43 Category: Jamb Chemistry 2013 15. $$\text{The solvent used for removing grease stains is}$$ a) $$\text{Turpentine}$$ b) $$\text{Ammonia solution}$$ c) $$\text{Ethanol}$$ d) $$\text{Solution of borax in water}$$ $$\text{Turpentine is a non-polar solvent, ideal for dissolving grease.}$$ 16 / 43 Category: Jamb Chemistry 2013 16. $$\text{In a water body, too much sewage leads to}$$ a) $$\text{Decrease in water temperature, causing aquatic death}$$ b) $$\text{Increase in aquatic animals}$$ c) $$\text{Increase in bacteria reducing oxygen levels}$$ d) $$\text{Decrease in bacteria increasing oxygen levels}$$ $$\text{Sewage increases bacteria, depleting oxygen, harming aquatic life.}$$ 17 / 43 Category: Jamb Chemistry 2013 17. $$10 \text{ dm}^3 \text{ of water was added to } 2.0 \text{ mol dm}^{-3} \text{ of 2.5 dm}^3 \text{ solution of HCl. Find the final concentration.}$$ a) $$0.4$$ b) $$8.0$$ c) $$2.0$$ d) $$0.5$$ $$\text{Dilution formula: } C_1V_1 = C_2V_2. C_2 = \frac{2.0 \times 2.5}{2.5 + 10} = 0.4 \text{ mol dm}^{-3}. $$ 18 / 43 Category: Jamb Chemistry 2013 18. $$\text{Three drops of 1.0 mol dm}^{-3} \text{ HCl are added to 20 cm}^3 \text{ of solution pH 6.4. The pH will be}$$ a) $$\text{Close to pure water}$$ b) $$\text{Less than 6.4}$$ c) $$\text{Greater than 6.4}$$ d) $$\text{Unaltered}$$ $$\text{Addition of strong acid reduces pH below 6.4, as H}^+ \text{ increases.}$$ 19 / 43 Category: Jamb Chemistry 2013 19. $$\text{Which of the following substances is not a salt?}$$ a) $$\text{Aluminium oxide}$$ b) $$\text{Sodium hydrogen trioxosulphate (V)}$$ c) $$\text{Sodium trioxocarbonate (V)}$$ d) $$\text{Zinc chloride}$$ $$\text{Aluminium oxide is an amphoteric oxide, not a salt.}$$ 20 / 43 Category: Jamb Chemistry 2013 20. $$\text{An insoluble salt can be prepared by}$$ a) $$\text{Reaction of trioxocarbonate (V) with acid}$$ b) $$\text{Double decomposition}$$ c) $$\text{Dilute acid on an insoluble base}$$ d) $$\text{Reaction of metals with acid}$$ $$\text{Double decomposition forms insoluble salts, e.g., PbSO}_4. $$ 21 / 43 Category: Jamb Chemistry 2013 21. $$2 \text{H}_2\text{O}(\ell) + 2\text{F}_2(\text{g}) \rightarrow 4 \text{HF}(\text{aq}) + \text{O}_2(\text{g}) \text{. The reduced substance is}$$ a) $$\text{O}_2(\text{g})$$ b) $$\text{H}_2\text{O}(\ell)$$ c) $$\text{F}_2(\text{g})$$ d) $$\text{HF}(\text{aq})$$ $$\text{F}_2 \text{ is reduced to HF by gaining electrons.}$$ 22 / 43 Category: Jamb Chemistry 2013 22. $$\text{Zn (s) + CuSO}_4(\text{aq}) \rightarrow \text{ZnSO}_4(\text{aq}) + \text{Cu (s). The oxidizing agent is}$$ a) $$\text{CuSO}_4(\text{aq})$$ b) $$\text{ZnSO}_4(\text{aq})$$ c) $$\text{Cu (s)}$$ d) $$\text{Zn (s)}$$ $$\text{CuSO}_4 \text{ (Cu}^{2+}) \text{ is reduced to Cu, acting as the oxidizing agent.}$$ 23 / 43 Category: Jamb Chemistry 2013 23. $$\text{In an endothermic reaction, if there is a loss in entropy, the reaction will}$$ a) $$\text{Be indeterminate}$$ b) $$\text{Be spontaneous}$$ c) $$\text{Not be spontaneous}$$ d) $$\text{Be at equilibrium}$$ $$\text{Endothermic reactions with entropy loss are non-spontaneous.}$$ 24 / 43 Category: Jamb Chemistry 2013 24. $$2 \text{SO}_2(\text{g}) + \text{O}_2(\text{g}) \rightleftharpoons 2 \text{SO}_3(\text{g}), \Delta H = -395.7 \text{kJ/mol. Increase } \text{SO}_3 \text{ by}$$ a) $$\text{Decreasing pressure}$$ b) $$\text{Decreasing temperature}$$ c) $$\text{Increasing temperature}$$ d) $$\text{Adding catalyst}$$ $$\text{Lower temperature favors exothermic reactions, increasing } \text{SO}_3 \text{ yield.}$$ 25 / 43 Category: Jamb Chemistry 2013 25. $$\text{The minimum energy required for a reaction to occur is called}$$ a) $$\text{Lattice energy}$$ b) $$\text{Ionization energy}$$ c) $$\text{Activation energy}$$ d) $$\text{Kinetic energy}$$ $$\text{Activation energy is the barrier that must be overcome for reaction.}$$ 26 / 43 Category: Jamb Chemistry 2013 26. $$\text{Which of the following compounds is a neutral oxide?}$$ a) $$\text{Carbon (IV) oxide}$$ b) $$\text{Sulphur (VI) oxide}$$ c) $$\text{Sulphur (IV) oxide}$$ d) $$\text{Carbon (II) oxide}$$ $$\text{Carbon (II) oxide is a neutral oxide, showing neither acidic nor basic properties.}$$ 27 / 43 Category: Jamb Chemistry 2013 27. $$\text{Which of the following gases is used as an anesthetic?}$$ a) $$\text{N}_2\text{O}$$ b) $$\text{NO}_2$$ c) $$\text{NH}_3$$ d) $$\text{NO}$$ $$\text{Nitrous oxide (N}_2\text{O) is commonly used as an anesthetic gas.}$$ 28 / 43 Category: Jamb Chemistry 2013 28. $$\text{Sulphur (IV) oxide is a strong reducing agent in water due to the formation of}$$ a) $$\text{Hydroxide ion}$$ b) $$\text{Sulphur (VI) oxide}$$ c) $$\text{Hydrogen sulphide}$$ d) $$\text{Trioxosulphate (IV) salt}$$ $$\text{Sulphur (IV) oxide reacts to form trioxosulphate (IV) salts, enabling reduction.}$$ 29 / 43 Category: Jamb Chemistry 2013 29. $$\text{A metal that forms soluble trioxosulphate (IV) salts is}$$ a) $$\text{Barium}$$ b) $$\text{Potassium}$$ c) $$\text{Manganese}$$ d) $$\text{Aluminium}$$ $$\text{Potassium forms soluble salts, unlike barium or aluminium.}$$ 30 / 43 Category: Jamb Chemistry 2013 30. $$\text{Copper is displaced from its salts by other metals because it}$$ a) $$\text{Is a transition element}$$ b) $$\text{Is at the bottom of activity series}$$ c) $$\text{Is very reactive}$$ d) $$\text{Has filled 3d orbitals}$$ $$\text{Copper’s low reactivity allows it to be displaced by more active metals.}$$ 31 / 43 Category: Jamb Chemistry 2013 31. $$\text{Transition metals have colored ions due to partially filled}$$ a) $$\text{F-orbital}$$ b) $$\text{S-orbital}$$ c) $$\text{P-orbital}$$ d) $$\text{D-orbital}$$ $$\text{D-orbital electrons absorb visible light, causing characteristic colors.}$$ 32 / 43 Category: Jamb Chemistry 2013 32. $$\text{Aluminium containers are often used for trioxonitrate (V) acid because aluminium}$$ a) $$\text{Has a silvery-white appearance}$$ b) $$\text{Has a low density}$$ c) $$\text{Does not react with acid}$$ d) $$\text{Does not corrode}$$ $$\text{Aluminium forms a protective oxide layer, preventing reaction with acid.}$$ 33 / 43 Category: Jamb Chemistry 2013 33. $$2\text{-Methylbutan-2-ol is an example of a}$$ a) $$\text{Dihydric alkanol}$$ b) $$\text{Tertiary alkanol}$$ c) $$\text{Secondary alkanol}$$ d) $$\text{Primary alkanol}$$ $$\text{The structure of 2-methylbutan-2-ol has a tertiary carbon bonded to OH.}$$ 34 / 43 Category: Jamb Chemistry 2013 34. $$\text{The reaction between ammonia and ethyl ethanoate produces}$$ a) $$\text{Propanol and ethanamide}$$ b) $$\text{Propanol and propanamide}$$ c) $$\text{Ethanol and propanamide}$$ d) $$\text{Ethanol and ethanamide}$$ $$\text{Ammonia reacts with esters to form ethanol and ethanamide.}$$ 35 / 43 Category: Jamb Chemistry 2013 35. $$\text{Decarboxylation of ethanoic acid produces carbon (IV) oxide and}$$ a) $$\text{Methane}$$ b) $$\text{Ethane}$$ c) $$\text{Propane}$$ d) $$\text{Butane}$$ $$\text{Removing CO}_2 \text{ from ethanoic acid results in methane.}$$ 36 / 43 Category: Jamb Chemistry 2013 36. $$\text{The compound CH}_3\text{CH}_2\text{COOH is classified as an}$$ a) $$\text{Alkanone}$$ b) $$\text{Alkanoate}$$ c) $$\text{Alkanal}$$ d) $$\text{Alkanoic acid}$$ $$\text{Carboxylic acids are characterized by the } \text{-COOH} \text{ functional group.}$$ 37 / 43 Category: Jamb Chemistry 2013 37. $$\text{Which compound reacts with NaOH to form salt and water?}$$ a) $$\text{C}_6\text{H}_{12}\text{O}_6$$ b) $$\text{(CH}_3\text{)}_3\text{COH}$$ c) $$\text{CH}_3\text{CH}=\text{CH}_2$$ d) $$\text{CH}_3\text{CH}_2\text{COOH}$$ $$\text{Carboxylic acids like CH}_3\text{CH}_2\text{COOH react with bases to neutralize.}$$ 38 / 43 Category: Jamb Chemistry 2013 38. $$\text{The dehydration of ammonium salts of alkanoic acids produces}$$ a) $$\text{Alcohols}$$ b) $$\text{Amides}$$ c) $$\text{Ketones}$$ d) $$\text{Esters}$$ $$\text{Amides are formed by dehydration of ammonium salts of alkanoic acids.}$$ 39 / 43 Category: Jamb Chemistry 2013 39. $$\text{Which fraction is used as a raw material in cracking processes?}$$ a) $$\text{Kerosene}$$ b) $$\text{Lubricating oil}$$ c) $$\text{Bitumen}$$ d) $$\text{Diesel oils}$$ $$\text{Diesel oils and heavy fractions are cracked to lighter hydrocarbons.}$$ 40 / 43 Category: Jamb Chemistry 2013 40. $$\text{An organic compound with a pleasant smell is likely to have the formula}$$ a) $$\text{CnH}_{2n+1}\text{CHO}$$ b) $$\text{CnH}_{2n+1}\text{COOH}$$ c) $$\text{CnH}_{2n+1}\text{COOCnH}_{2n+1}$$ d) $$\text{CnH}_{2n+1}\text{COCnH}_{2n+1}$$ $$\text{Esters have fruity smells and general formula } \text{CnH}_{2n+1}\text{COOCnH}_{2n+1}. $$ 41 / 43 Category: Jamb Chemistry 2013 41. $$\text{A primary amide is generally represented by}$$ a) $$\text{RCOOR}$$ b) $$\text{RCONH}_2$$ c) $$\text{RCONHR}$$ d) $$\text{RCONR}_2$$ $$\text{Primary amides have the functional group RCONH}_2\text{.}$$ 42 / 43 Category: Jamb Chemistry 2013 42. $$\text{The IUPAC nomenclature for CH}_3\text{CH}_2\text{C=CH}_2\text{ is}$$ a) $$\text{4-Methylpent-1-ene}$$ b) $$\text{3-Methylpent-2-ene}$$ c) $$\text{2-Methylpent-1-ene}$$ d) $$\text{2-Methylpent-4-ene}$$ $$\text{4-methylpent-1-ene has a double bond starting at the first carbon.}$$ 43 / 43 Category: Jamb Chemistry 2013 43. $$\text{An organic compound contains 60% C, 13.3% H, and 26.7% O. The empirical formula is}$$ a) $$\text{C}_5\text{H}_{12}\text{O}$$ b) $$\text{C}_3\text{H}_8\text{O}$$ c) $$\text{C}_6\text{H}_{13}\text{O}_2$$ d) $$\text{C}_4\text{H}_9\text{O}$$ $$\text{Simplified molar ratio: C=5, H=12, O=1. Empirical formula: C}_5\text{H}_{12}\text{O}. $$ Your score is The average score is 0% LinkedIn Facebook Twitter VKontakte 0% Restart quiz Anonymous feedback Send feedback
