hem!stry Name: lass: ate: / / rganic hemistry Multiple hoice Questions 1. n organic compound, X, has the empirical formula 24 and a relative molecular mass of 88. It reacts with ethanol in the presence of concentrated sulphuric acid to produce a sweet smelling liquid. Which one of the following structures could X have? 2. The conversion of ethanol into ethene is an example of: ydration. ehydrogenation. ehydration. Fermentation. 3. Which one of the following substances is formed when propan-1-ol (37) is oxidised by acidified sodium dichromate(vi) (Na2r27)? 38 36 37Na 25 1
2 4. The structure of butane maybe represented as: Which one of the following is an isomer of butane? 5. Which one of the following is the formula of an alkene? 4 26 38 48 6. Which one of the following is the formula of a possible product when ethanol (25) is oxidised? 24 26 25 3
7. It can be predicted from their formulae that the compounds: and have the same: Melting point. oiling point. Solubility in methylbenzene. omposition by mass. 8. Which one of the following is the correct formula for the ester formed when butanoic acid (322) reacts with methanol (3)? 3223 3223 323 3223 9. Which one of the following compounds has more than two carbon atoms per molecule? Ethyl ethanoate. Ethene. Ethanol. Ethane. 10. Fermentation is a process involving the conversion of: ydrocarbons to ethanol plus carbon monoxide gas. ydrocarbons to ethanol plus carbon dioxide gas. arbohydrates to ethanol plus carbon monoxide gas. arbohydrates to ethanol plus carbon dioxide gas. 11. The compound with the structure: 3 3 is a member of the homologous series of: cids. lcohols. lkanes. lkenes. 3
12. Which one of the following reagents is best suited to distinguishing between samples of ethane and ethene? lighted splint. queous bromine. queous barium nitrate. Lime water. 13. What is the number of isomers of formula 512? 1 2 3 4 14. What is the formula of the ester formed when propanoic acid reacts with ethanol? 253 33 2525 325 15. ctane is a member of the alkane homologous series. It has eight carbon atoms per molecule. What is its molecular formula? 88 810 814 818 16. ll members of a homologous series: ave the same empirical formula. ave the same melting points and boiling points. ave the same number of carbon atoms. Undergo similar chemical reactions. 17. Which one of the following does not change when ethene is polymerised to form poly(ethene)? Melting point. ensity. oiling point. Percentage composition. 4
18. Which one of the following statements concerning alkanes is correct? They undergo addition reactions. They have the same empirical formula. They occur naturally in crude oil. They react with organic acids to form esters. 19. What are the molecular formulae and empirical formulae of ethanoic acid? Molecular Formula 2 242 242 26 Empirical Formula 24 242 2 26 20. Four full structural formulae are shown below: 1. 2. 3. 4. Which of the above are possible structures for an alkene having the molecular formula 48? 1 and 4 only. 1, 2, 3 and 4. 1, 2 and 4 only. 2 and 3 only. 5
21. Ethanol vapour (Mr = 46) was bubbled through concentrated sulphuric acid. gas X was produced which decolourised bromine water. Which one of the following is the molecular formula of gas X? 4 24 26 36 22. Which one of the following correctly describes the properties of both ethane and ethene? They are both unsaturated hydrocarbons. They both readily decolourise bromine water. They are both readily polymerised. They can both burn to produce carbon dioxide and water. 23. ne mole of ethanol and one mole of ethene have an equal: Mass. Number of electrons. Number of atoms. Number of molecules. 24. What are the products of the fermentation of sugar? Ethanol and carbon dioxide. Ethanol and water. Ethanol and enzymes. arbon dioxide and enzymes. 6
25. Ethanol was oxidised to ethanoic acid using the apparatus shown below: The purpose of the condenser was to prevent the: onversion of the ethanol to ethene. Escape of any unreacted ethanol. Reforming of ethanol from the ethanoic acid. Reaction of the ethanoic acid with the ethanol. 26. Which one of the following equations represents the complete combustion of 37? 37 + 2 25 + 2 237 + 32 6 + 82 237 + 52 62 + 2 237 + 92 62 + 82 27. Which one of the following best describes the similarities and differences of compounds which are isomers? The Same hemical properties Physical properties Molecular formulae Structural formulae ifferent Molecular formulae hemical properties Structural formulae Molecular mass 7
28. The diagram below represents the process of fractional distillation of crude oil. t which position,,, or is bitumen obtained? 29. Ethanol is manufactured by a reaction between: Ethane and oxygen. ethene and oxygen. ethane and steam. ethene and steam. 30. What reacts at room temperature with ethanol and also with ethanoic acid? alcium carbonate. Methanol. opper(ii) oxide. Sodium. 31. What type of reaction occurs between ethene and hydrogen? ddition. Neutralisation. ehydration. xidation. 8
32. n organic compound Z reacts separately with sodium, sodium hydroxide and sodium carbonate. Which of the following can represent the structure of Z? 33. The structural formula of butenedioic acid is given below: Which one of the following statements about butanedioic acid is not correct? It is an unsaturated compound. Its empirical formula is the same as its molecular formula. Its relative molecular mass is 116. It decolourises bromine. 34. y what process is ethanol converted into ethanoic acid? istillation. Fermentation. Neutralisation. xidation. 35. What are the products when ethanol burns completely in air? arbon and steam. arbon dioxide and hydrogen. arbon dioxide and steam. arbon monoxide and steam. 9
36. Yeast can be used to convert simple sugars to: Ethanoic acid and oxygen. Ethanol and oxygen. Ethanol and carbon dioxide. Starch and carbon dioxide. 37. Five structural formulae are shown below: 2 3 1 4 5 Which of the formulae represent the same compound? 1, 2 and 4. 2 and 3 only. 2, 3 and 5. 2 and 4 only. 38. In which process do large molecules become smaller molecules? Fermentation of sugars. atalytic reaction between ethene and steam. Reaction between an alcohol and an organic acid. Reaction between ethene and bromine. 39. arbon dioxide and water are formed from poly(ethene) by: ddition. ombustion. Fermentation. Polymerisation. 10
40. Which structural formula represents an unsaturated hydrocarbon? l 41. The diagram shows the structural formulae of three compounds: Which statement is correct for all three compounds? They decolourise aqueous bromine. They are carbohydrates. They belong to the same homologous series. They are isomers of one another. 42. Ethanol is used in some perfumes and deodorants. Which pair of properties makes it suitable for these uses? It is flammable and mixes easily with water. It is flammable and vaporises easily. It is colourless and has a low freezing point. It is a good solvent and vaporises easily. 43. When glasses of wine or beer are left are left standing in the air for some time they become acidic. Which equation represents this change? 32 + 32 32 + 2 3 + 2 32 + 32 22 + 32 232 + 2 23 + 22 11
44. Which substance, present in car exhaust fumes, is not produced by the combustion of hydrocarbons? arbon. arbon dioxide. arbon monoxide. xides of nitrogen. 45. Which statement about the members of a homologous series is correct? They have the same empirical formula. They have the same melting point. They have the same number of carbon atoms per molecule. They undergo similar reactions. 46. Ethene reacts with steam at 300 in the presence of phosphoric acid as a catalyst. What is formed? Ethane. Ethanoic acid. Ethanol. Ethyl ethanoate. 47. ne mole of a hydrocarbon X reacted completely with one mole of hydrogen gas in the presence of a heated catalyst. What could the formula of X be? 26 38 510 716 48. The diagrams show the structures of four organic molecules: P Q R S Which two are members of the same homologous series? P and Q P and R P and S Q and R 12
49. The taste of wine changes after contact with air because some of the alcohol in the wine: Evaporates. Ferments. Reacts with carbon dioxide. Reacts with oxygen. 50. The formula of butanol may be written as 49. The next higher member of the homologous series of alcohols is pentanol. ow may the formula of pentanol be written? 48()2 49()2 59 511 51. Which of the following statements about the homologous series of alcohols is not true? They can be prepared by similar methods. They can be represented by a general formula. They exhibit a gradual change of physical properties. They all contain oxygen. 52. What is the product formed when hydrogen reacts with an alkene? n alcohol. n alkane. carbohydrate. n organic acid. 53. n organic acid X decolourises aqueous bromine. Which formula could represent X? 13
14 54. n organic compound Z reacts both with sodium hydroxide and with sodium carbonate. What could the structure of Z be? 55. The graph shows the proportion of methane in a coal mine during a working day: What is most likely to have caused the sudden fall in the percentage methane shown on the graph? The temperature in the mine was lowered. n explosive mixture of methane and air ignited. The ventilator fans were switched on. Methane stopped seeping into the mine. 56. Ethane gas was cracked to produce hydrogen gas and another gas Y which decolourised aqueous bromine. What is the structural formula of Y?
57. The table shows how many moles of products are formed by the complete combustion of four hydrocarbons. Which hydrocarbon requires 11 moles of oxygen gas (2) for this combustion? ydrocarbon Moles of 2 Moles of 2 38 512 612 716 3 4 5 6 6 6 7 8 58. Which of the following is an ester? Nylon. PV. Soap. Terylene. 59. Which one of the following does not occur in the complete combustion of ethane in a plentiful supply of air? reaking of carbon-to-carbon bonds. reaking of carbon-to-hydrogen bonds. reaking of carbon-to-oxygen bonds. Forming of carbon-to-oxygen bonds. 60. The diagram shows four stages in a reaction scheme: Stage Stage Stage Stage Petroleum ctane Ethene Ethanol t which stage does catalytic cracking take place? Ethanoic acid 15
61. In the alkane series of hydrocarbons (n2n+2) the boiling point (b.p.) of the compound increases as n increases. Which graph correctly represents this effect? 62. Which set contains the correct process for converting substance S to the product(s)? Substance S Process Products Ester ddition polymerisation Terylene Starch ondensation polymerisation Glucose Protein ydrolysis mino acids Ethanol Reduction Ethanoic acid 63. In the fractional distillation of crude oil, which product has the highest boiling point? itumen. Paraffin (kerosene). Lubricating oil. Petrol (gasoline). 64. n aqueous solution of a compound of molecular formula 242 reacts with sodium carbonate liberating carbon dioxide. What is the structural formula of the compound? 16
65. 10 cm 3 sample of gaseous hydrocarbon was completely burnt in oxygen. The total volume of the product was 70 cm 3. Which equation represents the combustion of the hydrocarbon? 4(g) + 22(g) 2(g) + 22(g) 24(g) + 32(g) 22(g) + 22(g) 38(g) + 52(g) 32(g) + 42(g) 226(g) + 72(g) 42(g) + 62(g) 66. Which structural formula represents an unsaturated hydrocarbon? l 67. What is the formula of the ester formed when propanoic acid (32) reacts with ethanol? 323 33 3223 323 68. Which statement about ethanol is correct? It is formed by the catalytic addition of steam to ethene. It is an unsaturated compound. It is formed by the oxidation of ethanoic acid. It reacts with ethyl ethanoate to form an acid. 69. Ethanol is manufactured by the reaction between: Ethane and oxygen. Ethane and steam. Ethene and oxygen Ethene and steam. 17
70. In how many of the following can paraffin (kerosene) be used as the energy source? ircraft ir onditioning Units ars omestic ooking eavy Lorries Power Stations 1 2 3 4 71. Which statements are true about alkanes? 1 Their general formula is n2n. 2 They are flammable. 3 They react with chlorine. 1 and 2 only. 2 and 3 only. 1 and 3 only. 1, 2 and 3. 72. The reaction between a carboxylic acid, xy2, and an alcohol, n2n+1, produces an ester. ow many hydrogen atoms does one molecule of the ester contain? y + 2n y + 2n + 1 y + 2n + 2 y + 2n + 3 73. Which compound will react with steam, in the presence of a catalyst, to produce the alcohol 3222? 322 3223 3=2 32=2 74. In which reaction does the product have more carbon atoms than the underlined reactant? carboxylic acid produced from an alcohol and an oxidising agent. n ester produced from a carboxylic acid and an alcohol. salt produced from a carboxylic acid and sodium carbonate. arbon dioxide produced from the complete combustion of propane in oxygen. 18
75. ompound X can be oxidised to compound Y. ompound X ompound Y What are compound X and compound Y? X utanol Ethanol Propanol Propanol Y Propanoic cid Ethanoic cid Ethanoic cid Propanoic cid 76. ne mole of a hydrocarbon X reacted completely with one mole of hydrogen gas in the presence of a heated catalyst. What could be the formula of X? 26 38 510 716 77. n ester of molecular formula 482 was produced by the reaction of an alcohol with a carboxylic acid. 1 2 3 lcohol Methanol Ethanol Propanol cid Propanoic cid Ethanoic cid Methanoic cid Which of the following could be the alcohol and the acid? 1, 2 and 3 1 and 2 only. 1 and 3 only. 2 only. 19
78. Pentanoic acid has the formula 32222. Which formula represents butyl pentanoate? 3 2 2 2 2 2 3 3 2 2 2 2 2 2 2 3 3 2 2 2 2 2 3 3 2 2 2 2 2 2 3 79. There are two isomers of butene, 48, their structures are given below: 2=23 and 3=3 ow many statements about these two isomers are correct? ombustion of 1 mole of each produces equal numbers of moles of 2 and 2. oth decolourise bromine water. oth produce the same molecule when reacted with bromine. oth produce the same molecule when reacted with hydrogen. When polymerised, the same polymer is produced. 2 3 4 5 80. If one mole of each alcohol is burnt in excess oxygen, which alcohol will provide 2 and 2 in a mole ratio of 3:4? 3 25 37 49 20
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