Chem Alcohol and Organic Acids AfL

Secondary 4 Express Chemistry – Alcohol and Organic Acids - 1 - Name: _______________________ Date: _________________ Class: _____________________ Section A: Multiple Choice Questions 1 Which of the following is the general formula of an organic acid? A CnH2n + 2CO2H B C nH2n + 1CO2H C CnH2n - 1CO2H D C nH2nOn 2 Which of the following is the general formula of an alcohol? A CnH2n + 2OH B C nH2n + 1OH C CnH2n - 1OH D C nH2nO 3 The structural formulae of three compounds X, Y and Z are shown below. X Y Z H H H H H H H H H H C C C O H H C C C H H C O C C H H H H H O H H H H H Which compounds are isomers? A X and Y only B X and Z only C X, Y and Z D Y and Z only 4 What is the same for ethanol, ethanoic acid and ethyl ethanoate? A the elements in each compound B the empirical formula of each compound C the number of carbon atoms in one molecule of each compound D the number of oxygen atoms in one molecule of each compound

Secondary 4 Express Chemistry – Alcohol and Organic Acids - 2 - 5 Ethanoic acid can be produced from glucose as follows. Stage I Stage II Glucose Ethanol Ethanoic Acid Which terms are used to describe these two stages? Stage I Stage II A cracking oxidation B fermentation oxidation C fermentation addition D oxidation fermentation 6 What are the empirical and molecular formulas of ethanoic acid? empirical formula molecular formula A CH2O C2H4O2 B C2H4O C2H4O C C2H6O C2H6O D C2H4O2 CH2O 7 The diagram shows the structure of a compound Q. O O H O C H H C O H H C C C C H H H How can compound Q be classified? A as an acid and an alcohol B as an acid and as an alkene C as an alcohol and as an alkene D as an ester and as an alkene

Secondary 4 Express Chemistry – Alcohol and Organic Acids - 3 - 8 Four isomers of C2H4O2 are shown below. Which one reacts with sodium carbonate to produce carbon dioxide gas? A B C D H H O H H H H O H H C O C H C C H H C O C C C H O O H H O H O H 9 Which two properties explain why ethanol is suitable for use in perfumes and deodorants? A It is flammable and is a good solvent. B It is colourless and is flammable. C It is a good solvent and has a low boiling point. D It is flammable and has a low boiling point. 10 Ethanol is boiled with excess acidified potassium dichromate(VI). What is the organic product? A ethane B ethanoic acid C ethyl ethanoate D polyethene 11 Organic compound X reacts with sodium hydroxide to produce a compound with molecular formula C4H9O2Na. What can X be? A butanol B butane C butanoic acid D butene

Secondary 4 Express Chemistry – Alcohol and Organic Acids - 4 - 12 The structural formulas of two compounds are shown below. H H O H H H H O H C C C O C H H C C C C H H H H H H O H What are the similarities and differences between these two compounds? similarities differences A molecular formulas relative molecular masses B structural formulas molecular formulas C molecular formulas chemical reactions D structural formulas relative molecular masses Section B: Structured Questions 1 Some information about some alcohols is given in the table. name relative molecular mass, Mr boiling point, oC heat produced on completely burning one mole, kJ methanol 32 65 720 ethanol 78 1370 60 97 2010 butanol 74 2670 pentanol 88 138 (a) Complete the table by (i) adding the name of the other alcohol (ii) calculating the missing relative molecular mass (iii) estimating the boiling point of butanol (iv) estimating the heat produced on completely burning one mole of pentanol. [4]

Secondary 4 Express Chemistry – Alcohol and Organic Acids - 5 - (b) Complete the equation for the complete combustion of butanol. C4H9OH + O2  + ; H = .......... ............. ............. ......................... [2] (c) Explain why the data for the heat produced in burning one mole increases down the table. ................................................................................................................................ ................................................................................................................................. [1] 2 A list of formulas of several organic compounds is given below. C2H5OH C5H10 C3H7COOH C8H18 C3H8 Choose from these formulas, the ones that fit the descriptions below. (a) a compound that undergoes an addition reaction with steam ............................................................................................. [1] (b) a compound that has a pH less than 7 in water ........................................................................................…... [1] (c) a compound that is oxidised by air to produce ethanoic acid ........