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Question 80: [Organic > Carboxylic Acids and Derivatives] Mevalonic acid is an intermediate in the biosynthesis of cholesterol, and is shown below. Which properties does mevalonic acid have? 1 It has only 1 chiral carbon atom. 2 It can be esterified both by ethanoic acid and by ethanol, in the presence of H+ ions. 3 It contains both...
Question 79: [Organic > Hydroxyl Compounds] When the apparatus below was used with compound Z, a brick-red precipitate formed in the right-hand tube. Which compound could be Z? 1 CH3CH(OH)CH3 2 CH3CH2CH2OH 3 CH3OH Reference: Past Exam Paper –June 2003 Paper 1 Q39 Solution 119: Answer: C. 1, 2 and 3 are all alcohols. When an alcohol is presented...
Question 70: [Organic > Carbonyl Compounds] The product of the reaction between propanone and hydrogen cyanide is hydrolysed under acidic conditions. What is the formula of the final product? A CH3CH(OH)CO2H B CH3CH2CH2CO2H C (CH3)2CHCONH2 D (CH3)2C(OH)CO2H Reference: Past Exam Paper –June 2003 Paper 1 Q30 Solution 70: Answer: D. First observe the formula for propanone: (CH3)2C=O. The reactants...
Question 69: [Organic > Hydroxyl Compounds] In a preparation of ethene, ethanol is added a drop at a time to a heated reagent Y. To purify the ethane it is bubbled through a solution Z and then collected. What could reagent reagent Y and solution Z be? reagent Y solution Z A acidified K2Cr2O7 dilute NaOH B concentrated...
Question 68: [Organic > Carbonyl Compounds] In its reaction with sodium, 1 mol of a compound X gives 1 mol of H2(g). Which compound might X be? A CH3CH2CH2CH2OH B (CH3)3COH C CH3CH2CH2CO2H D CH3CH(OH)CO2H Reference: Past Exam Paper –June 2003 Paper 1 Q28 Solution 68: Answer: D. 1 alcohol group reacts with 1 Na atom to produce 1...
Question 67: [Organic > Halogen Derivatives] Chlorofluoroalkanes, commonly known as CFCs, undergo homolytic fission by ultraviolet irradiation in the stratosphere. Which radical could result from the irradiation of CHFClCF2Cl? A CHFClĊFCl B ĊHClCF2Cl C ĊHFCF2Cl D ĊFClCF2Cl Reference: Past Exam Paper –June 2003 Paper 1 Q27 Solution 67: Answer: C. In the given CFC above, there are C-H bonds,...
Question 66: [Organic > Halogen Derivatives] The reaction scheme outlines the production of one of the monomers of nylon 66 from compound X. Which compound could be X? A BrCH2CH2CH2CH2Br B CH2=CHCH=CH2 C HOCH2CH2CH2CH2OH D HO2CCH2CH2CH2CH2CO2H Reference: Past Exam Paper –June 2003 Paper 1 Q26 Solution 66: Answer: A. In option A, the halogenoalkane has Br atoms which are...
Question 65: [Organic > Carbonyl Compounds] Which reaction is not an electrophilic addition? A CH2=CH2 + HI à CH3CH2I B CH3CH=CH2 + Br2 à CH3CHBrCH2Br C CH3CH=CH2 + H2O à CH3CH(OH)CH3 D CH3CHO + HCN à CH3CH(OH)CN Note: in option C there is a catalyst - conc H2SO4 Reference: Past Exam Paper –June 2003 Paper 1 Q25 Solution 65:...
Question 64: [Organic > Halogen Derivatives] Cyclohexa-1,4-diene is treated with a solution of bromine in tetrachloromethane. Reference: Past Exam Paper –June 2003 Paper 1 Q24 Solution 64: Answer: B. Double bond present on the right and left sides of cyclohexa-1,4diene. They undergo electrophilic addition due to presence of bromine molecules. 4 carbon atoms on the sides are unsaturated, where...
Question 103: [Organic > Hydrocarbons] The complete combustion of alkanes to produce carbon dioxide and water is an important exothermic reaction. Which line on the graph shows the relationship between the number of carbon atoms in the alkane and the number of moles of oxygen gas needed for complete combustion of the alkane? Reference: Past Exam Paper –June 2003...
