AlcoholsCnH2n+1OHCombustion heats of alcoholsname physical state combustion heat kj/molMethanol liquid -729

Ethanol liquid -1372

Propanol liquid -2022

Propan-2-ol liquid -1994

Butanol liquid -2680

Pentanol liquid -3330

Hexanol liquid -3985

Heptanol liquid -4630

Octanol liquid -5287

Comparing The Methods Of Producing Ethanol

fermentation(Brazil) hydration of ethene

C6H12O6(aq) 2C2H5OH(aq)+CO2(g) CH2=CH2(g)+H2O(g) C2H5OH(aq)

yeast,370C 3000C,60 atm

anaerobic conditions catalyst H3PO4

Type of Batch process using fixed Continuous process, ethene and

process amounts of sugary solution steam fed in continually

Raw Sugar (or starch) a renewable Ethene from cracking crude oil

Material resource a finite resource (disadvantage)

Rate of Slow -process takes days Fast –process is catalyzed at

reaction if not weeks high temperature and pressure

Quality of Percentage of ethanol is low, 100% ethanol can readily be produced

product flavor is more important

Use of Alcoholic drinks, beers, Industrial solvent and fuel

Product wines and sprits

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1 What is produced when ethanol is boiled with an excess of acidified potassium dichromate(VI)?

A ethane B ethanoic acid C ethene D ethyl ethanoate

2 The structure of butan-1-ol is shown.

Which structure is an isomer of that shown above?

3 Which pair of structures are isomers of each other?

4 The diagram represents an organic compound that contains three different elements.What could be the compound?

A ethanoic acid B ethanol C propane D propene

5 Vinegar is a solution of ethanoic acid made by the reaction of ethanol with air.Which gas in air takes part in this reaction?A carbon dioxide B nitrogen C oxygen D water vapour

6 Which statement is true about ethanol?A It is formed by the catalytic addition of steam to ethene.B It is an unsaturated compound.C It is formed by the oxidation of ethanoic acid.D It reacts with ethyl ethanoate to form an acid.

7 For complete combustion, one molecule of an organic compound needs 8 molecules of oxygen.What could the formula of this compound be?A C5H11OH B C6H9OH C C6H11OH D C6H12

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8 The apparatus shown was set up to prepare ethanoic acid from ethanol.

What was the purpose of the condenser?A to make sure air does not react with ethanolB to stop ethanoic acid changing back to ethanolC to stop ethanol being converted into etheneD to stop ethanol vapour escaping

9 The diagram shows the steps by which carbon dioxide can be converted into organic products and finally returned to the atmosphere.Which step is endothermic?

10 The structures of three compounds P, Q and R are shown.

Which compounds are isomers of each other?A Pand Q only B Pand R onlyC Qand R only D P, Q and R

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11 Compound Q has the structure shown.

Which structure is an isomer of Q?

12 Compound X has the molecular formula C2H6O.• X can be made by a fermentation process.• X can be oxidised to Y.• X can react with Y to form Z and water.

To which homologous series do X, Y and Z belong?X Y Z

A alcohols carboxylic acids estersB alcohols esters carboxylic acidsC carboxylic acids alcohols estersD carboxylic acids esters alcohols

13 The list shows reactions in which ethanol is either a reactant or a product.1234

combustion of ethanolconversion of ethene to ethanolfermentation of glucoseoxidation of ethanol to ethanoic acid

In which reactions is water also either a reactant or a product?A 1, 3 and 4 only B 2, 3 and 4 only C 1, 2 and 4 only D 3 only

14 Which of the reactions X, Y and Z involve oxidation?

A X only B X and Y C Y only D Y and Z

15 Ethanol may be made by growing yeast in sugar solution.The process is called(a) combustion, (b) cracking, (c) esterification, (d) fermentation.

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16 The molar heat of combustion, i.e. the heat given out when one mole of the alcohol is completely burned in oxygen, of a number of alcohols is given below.

alcohol formula heat of combustion kJ/molmethanol CH3OH 750ethanol C2H5OH 1380

propanol C3H7OH 2010butanol C4H9OH 2640

How many carbon and hydrogen atoms would there be in an alcohol that has a molar heat ofcombustion of 3900 kJ / mol?

number of carbon atoms number of hydrogen atomsA 5 11B 5 12C 6 13D 6 14

17 A compound known in industry as ‘MTBE’ is used as an additive in ‘lead-free’ petrol. Thestructural formula of MTBE is shown.

Which compound is an isomer of MTBE?

18 Properties of some organic compounds include:1 they burn;2 they dissolve in water;3 they polymerise.

Which of these properties does ethanol have?1 2 3

A

B

C

D

19Which of the following changes can occur when the first named substance reacts withacidified potassium manganate(VII)?(a) ethanoic acid ethanol(b) ethanol ethyl ethanoate(c) ethyl ethanoate ethene(d) ethanol ethanoic acid

20 A student converted starch into ethanol by a process involving two stages. An acid was usedin stage A and yeast in stage B. A B STARCH SUGAR ETHANOLWhat are the stages A and B? A B(a) distillation esterification(b) distillation fermentation

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(c) hydrolysis esterification(d) hydrolysis fermentation

21 A student used the apparatus below to produce a solvent (alcohol) from fermented sugasolution.

(a) Name and give the formula of the alcohol.(i) name...........................................................................................................................................................(ii) formula ...................................................................................................................................................... (b) What must also be present in the original sugar solution to cause fermentation to takeplace?........................................................................................................................................................................ (c) How did the student know when all the alcohol had been distilled?........................................................................................................................................................................Half of the alcohol was transferred to a flask and some acidified potassium dichromate(VI) wasadded. The mixture was warmed.(d) (i) What was the colour change during the reaction?from .......................................................................... to .................................................................................(ii) What was the organic product of this reaction?........................................................................................................................................................................ The compound from (d)(ii) was separated from the reaction mixture. It was addedto the other half of the alcohol from (c). A few drops of concentrated sulphuric acidwere added and the mixture was warmed.(e) (i) Name and give the formula of the organic compound formed.name ..............................................................................................................................................................formula ...........................................................................................................................................................(ii) To which group of organic compounds does this product belong?........................................................................................................................................................................

22 The alcohols form a homologous series. The first four members are methanol, ethanol,propan-1-ol and butan-1-ol.(a) One characteristic of a homologous series is that the physical properties vary in apredictable way. The table below gives the heats of combustion of the first threealcohols.

alcohol formula Heat of combustion in kJ/molmethanol CH3OH -730ethanol CH3CH2OH -1370propen-1-ol CH3CH2CH2OH -2020butan-1-ol CH3CH2CH2CH2OH

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(i) The minus sign indicates that there is less chemical energy in the products than inthe reactants. What form of energy is given out by the reaction? (ii) Is the reaction exothermic or endothermic? (iii) Complete the equation for the complete combustion of ethanol.

C2H5OH + O2 →…………………………….. +……………………………………………………(iv) Determine the heat of combustion of butan-1-ol by plotting the heats of combustionof the first three alcohols against the number of carbon atoms per molecule.

number of carbon atoms per molecule

The heat of combustion of butan-1-ol =…………………………………………………. kJ / mol(v) Describe two other characteristics of homologous series.b) Give the name and structural formula of an isomer of propan-1-ol.structural formula………………………………………………………………………………………………………name ……………………………………………………………………………………………………………………c) Methanol is made from carbon monoxide.

CO(g) + 2H2(g) CH3OH(g) the forward reaction is exothermic(i) Describe how hydrogen is obtained from alkanes. (ii) Suggest a method of making carbon monoxide from methane. (iii) Which condition, high or low pressure, would give the maximum yield of methanol?Give a reason for your choice.Pressure………………………………………………………………………………………………………………..Reason…………………………………………………………………………………………………………………. d) For each of the following predict the name of the organic product.(i) reaction between methanol and ethanoic acid

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(ii) oxidation of propan-1-ol by potassium dichromate(VI) (iii) removal of H2O from ethanol (dehydration)

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