Chemistry Questionsheets A2 Level-Books Pdf

CHEMISTRY QUESTIONSHEETS A2 Level
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A2 Level TOPIC 28 Questionsheet 1,SYNOPTIC QUESTION 1. Acid base equilibria pH H buffers,Isomerism optical. Qualitative organic analysis OH,Calculation volumetric analysis formula. mass composition, In order to reduce tooth decay it is recommended that the intake of sugar containing food and drink is reduced and also. that teeth and gums be cleaned regularly especially after meals After eating the pH level in the mouth can change from. the normal level of about 6 75 to around 4 5 due to the breakdown of sugars into acids such as lactic acid CH3CHOHCOOH. Sugar in food Organic acids e g CH3CHOHCOOH, The pH value of about 4 5 may remain at this level in the mouth for up to 20 minutes during which time the tooth enamel.
is being attacked and demineralised by the acids present However hydrogencarbonate ions HCO3 present in saliva. introduce a buffering action and the pH value returns to normal in approximately 1 to 2 hours Chewing sugar free gum. stimulates the production of extra saliva and its use after meals when brushing is not possible may help to reduce tooth. decay by returning the pH levels back to normal in a shorter time. a i Calculate the H ion concentration at pH 6 75 and at pH 4 5 2. ii Calculate the percentage increase in the H ion concentration 2. iii Explain how the hydrogencarbonate ions act as a buffering agent in the reduction of the H ion. concentration 2, b Lactic acid 2 hydroxypropanoic acid exhibits the property of optical isomerism Illustrate and explain the. origin of this property by showing the structures of its two optical isomers 4. c One of the ingredients present in the sugar free gum is the sweetener sorbitol CH2OH CHOH 4CH2OH. i Describe with a suitable equation and the expected observations a simple test to show the presence of the. hydroxyl group OH in a sample of solid sorbitol 4, ii What must be assumed about the sorbitol to make this a reliable test 1. d The disodium salt of EDTA ethylenediaminetetra acetic acid forms stable complexes with many metal ions and can. be used as a titrimetric reagent for estimating the concentrations of such ions 1 00 g of tooth enamel was dissolved in. acid and made up to a total volume of 250 cm3 with distilled water A 25 cm3 sample of this solution was then adjusted. to a pH of 12 with a buffer solution and titrated with a 0 1 mol dm 3 EDTA solution After several titrations an average. of 9 45 cm3 of the EDTA solution were required to reach the end point. Given that the reaction between calcium ions and EDTA is represented by the equation. Ca2 H2EDTA2 Ca EDTA 2 2H, calculate the percentage by mass of calcium in tooth enamel 5. e Tooth enamel is reported to consist of 95 by mass of basic calcium phosphate of formula Ca10 PO4 6 OH 2. Show by calculation whether or not your answer to d is consistent with this formula 3. f From the formula given in e suggest why tooth enamel dissolves in acid 2. g The use of chewing gum is said to be dangerous to animals Suggest a reason 1. A2 Level TOPIC 28 Questionsheet 2,SYNOPTIC QUESTION 2. Redox equations,Transition metal properties,Isotope percentage and relative atomic mass.
Carbon monoxide formation and treatment, Smoke alarms and to some extent carbon monoxide detectors are present in many homes. and other places where people reside, In addition a small detector may sometimes be seen placed on a wall close to a gas appliance. such as a fire or water heater, This type of detector contains a small area of orange coloured crystals that darken when. exposed to carbon monoxide The coloured area contains orange palladium chloride crystals. together with copper II chloride When exposed to carbon monoxide the palladium chloride. is changed into dark grey palladium metal,CO PdCl2 2H2O CO2 Pd 2HCl H2O Equation 1. When the air is free of carbon monoxide the palladium chloride is regenerated by the copper II chloride. Pd 2CuCl2 2H2O PdCl2 2H2O 2Cu Cl 2H2O Equation 2,The final stage is.
2Cu Cl 2HCl 3H2O O2 2CuCl2 2H2O Equation 3, a Explain with a suitable equation how carbon monoxide is released from appliances using natural gas 2. b Why is it essential to be warned of the presence of carbon monoxide in enclosed spaces and what is the. property of this gas that make such detectors necessary 2. c In terms of oxidation numbers explain why the reaction represented by Equation 1 is a redox reaction 2. d Palladium is a d block element In terms of its electronic structure why can it also be described as a. transition metal and which one of its transition metal properties explains its behaviour in Equations 1 2 2. e What single overall equation can be formed from the combination of Equations 1 2 and 3 2. f Palladium has six naturally occurring isotopes,Relative mass of isotope 102 104 105 106 108 110. Abundance 1 0 11 0 22 2 27 3 26 7 11 8, Calculate the relative atomic mass of palladium from this data 3. g i Name the technique used in obtaining the data in f 1. ii This method of analysis is used in drugs testing in sport space and medical research and environmental. monitoring What does this suggest about this technique 1. A2 Level TOPIC 28 Questionsheet 2 Continued,SYNOPTIC QUESTION 2. h Carbon monoxide is emitted in the exhaust gases of cars but the increasing use of catalytic converters results. in about a 90 reduction compared with cars not fitted with converters. Carbon monoxide,ignition Carbon dioxide 90 Carbon dioxide.
Hydrocarbons Nitrogen Nitrogen,Air Water Water,Nitrogen oxides. CO Al2O3 particles impregnated,HC with metal catalysts. ceramic monolith, By kind permission of The Open University OpenLearn http. openlearn open ac uk mod resource view php id 211955. Vehicle type CO g km 1, Typical urban emissions from European Petrol without catalyst 27 0. technology cars,Petrol with catalyst 2 0, Present European standards for passenger cars Petrol 2 2.
It has been estimated that 70 of the harmful emissions per journey are released in the first 80 seconds when the. catalyst is cold A platinum catalyst starts working at 240 C while a platinum rhodium alloy starts at about 150 C. i Why is the catalyst described as heterogeneous, ii Suggest why the catalyst is more effective when hot. iii Give reasons why the catalyst is in the form of a very thin layer on a ceramic support with a large surface area 5. A2 Level TOPIC 28 Questionsheet 3,SYNOPTIC QUESTION 3. Kc changes with temperature,Bond energy calculations for H. Effect of bonding on properties,Environmental problems from sulfur compounds. Crude oil contains a variable but significant percentage of sulfur compounds During the refining processes these. compounds are removed and converted into elemental sulfur As much as 100 tonnes of sulfur is recovered per day and. utilised by other chemical industries for example in the production of sulfuric acid. a Calculate the quantity of sulfuric acid that could be produced per day from this quantity of sulfur 2. b As part of the recovery process the sulfur compounds are converted into hydrogen sulfide This gas is then removed. by passing it at low temperature through an aqueous organic solvent Solv which forms an unstable complex. 2 Solv aq H2S g Solv 2 H2S aq, i Write an expression for the equilibrium constant Kc for this reaction and state its units 2.
ii At low temperatures the value of Kc is large but decreases as the temperature increases State what this. indicates about the nature of H for the reaction and give an explanation 4. c Sulfur is recovered from the hydrogen sulfide in a two stage process. 2H2S g 3O2 g 2H2O l 2SO2 g Equation 1,2H2S g SO2 g 2H2O l 3S s Equation 2. Given the following bond dissociation enthalpies kJ mol 1. H S 364 O O 498 H O 464 S O 497, calculate H values for both Equation 1 and Equation 2 and hence state whether the recovery of sulfur from. hydrogen sulfide is exothermic or endothermic 5, d Explain the differences in these values between these pairs of compounds. Compound Boiling point C,Hydrogen sulfide 61,Compound Bond angle. Hydrogen sulfide 92 2 H S H,Methane 109 3 H C H, e Small amounts of sulfur compounds do remain in liquid hydrocarbon fuels and when burnt lead to the formation of.
sulfur dioxide Catalytic converters reduce oxides of nitrogen back into nitrogen and at the same time also reduce the. sulfur dioxide into hydrogen sulfide This is often noticed as a bad egg smell from cold started engines In what ways. are these two sulfur compounds damaging to both health and the environment 3. f Outline an experiment that you could carry out in the laboratory using typical apparatus and reagents to enable. you to estimate the quantity of sulfur dioxide present in the atmosphere 4. Quality of language 1,A2 Level TOPIC 28 Questionsheet 4. SYNOPTIC QUESTION 4,Reaction order rate equation constant. Vegetable oils level of unsaturation uses,Condensation polymers. a The experimental study of the hydrolysis of the ester methyl methanoate in the presence of sodium hydroxide. produced the following data,Initial concentrations. Experiment Initial rate of reaction,at 25 C mol dm 3 s 1.
HCOOCH3 OH,1 0 050 0 050 0 00034,2 0 050 0 100 0 00068. 3 0 100 0 100 0 00136, i From the data deduce the order of the reaction with respect to both the methyl methanoate and the hydroxide ions. ii Hence write a rate equation for the reaction,iii Calculate the value of the rate constant 5. b Natural vegetable oils and animal fats are esters which are of economic importance because they can be used to. produce soap and foodstuffs such as margarine Vegetable oils are unsaturated compounds and the degree of. unsaturation is expressed by an iodine value Iodine adds across the double bond s. and the iodine value is the mass of iodine required to fully saturate 100 g of the oil An ester of relative molecular. mass 884 present in olive oil has an iodine value of 86 2. i Calculate the number of double bonds present in one molecule of the oil. ii State the reagents and conditions required to convert the oil into margarine and also into soap 8. c Polyesters form the basis of many fabrics currently in use. Terylene is formed by a condensation reaction between the following compounds. HOOC COOH and,HO CH 2 2 OH,By kind permission of ASOS marketing. i What is meant by the expression condensation reaction. ii Use the above two formulae to draw one repeating unit of the polymer. iii Name or draw the structure of a functional group that could be used instead of the carboxylic group COOH. d Over the last century fabric fibres have moved from natural sources such as wool to semi synthetic fibres based. on cellulose from wood pulp The latter processes were complex and used hazardous chemicals and were superseded. by fully synthetic materials from crude oil extracts. Suggest the environmental and economic advantages and disadvantages of returning to cellulose based fibres as the. life expectancy of known oil reserves reduces 4,Quality of language 1.
A2 Level TOPIC 28 Questionsheet 5,SYNOPTIC QUESTION 5. Titanium chemistry extraction,Chlorine disproportionation. The Born Haber Cycle, a Titanium metal is extracted from titanium IV oxide TiO2 This oxide is heated with coke in a stream of chlorine to. produce titanium IV chloride as a first stage in the process In the second stage after separation and purification. by distillation the titanium IV chloride is reduced with either magnesium or sodium in vacuo to produce the free. i Write balanced equations to represent the reactions taking place in the two stages mentioned above. ii Why is the reduction carried out in a vacuum, iii Why is this extraction method used rather than the direct reduction of the oxide by heating with coke. b Chlorine for this process can be obtained by the electrolysis of sodium chloride solution brine Give an ionic. equation for the reaction of chlorine with water and explain why this is a disproportionation reaction 3. c Titanium especially when alloyed with other metals such as aluminium has high strength low density and resistance. to corrosion In addition it is the second most abundant transition element and ninth most abundant of all the. elements State two reasons why titanium has limited use despite its unique properties and abundance 2. d i Use the following data to construct a Born Haber cycle and then calculate the lattice enthalpy of. titanium IV oxide,Enthalpy of atomisation of titanium 470.
Total ionisation energy for Ti g Ti4 g 8796,Enthalpy of atomisation of oxygen 249. Total electron affinity for O g O2 g 702,Enthalpy of formation of TiO2 s 940 5. ii With respect to the value of the lattice enthalpy of titanium IV oxide explain why it is an insoluble. solid with low reactivity 2, iii Titanium IV oxide and basic lead carbonate are both white solids which can be used as a pigment in paints. Give one contrasting property for these compounds that explains why titanium dioxide has now replaced the. lead compound for this use 2, e Titanium IV chloride has a melting point of 24 C and a boiling point of 136 5 C When used in conjunction. with triethylaluminum it acts as a heterogeneous catalyst for the production of high density poly ethene. i Which transition element property explains the catalytic behaviour of titanium IV chloride. ii What is understood by the term heterogeneous catalyst. iii Describe the bonding and structure of titanium IV chloride. iv When dissolved in concentrated hydrochloric acid titanium IV chloride forms an octahedral anion. Suggest a formula for this product ion and name the types of bond within it. A2 Level TOPIC 28 Questionsheet 6,SYNOPTIC QUESTION 6.
Enthalpy of solution,Born Haber Cycle for solution. Experimental determination of H,Instant Cold and Hot Packs. Athletes often use instant cold packs and hot packs as first aid devices. to treat injuries, These devices operate by utilising the concept of enthalpy of solution A. typical pack consists of a plastic bag containing a dry solid salt and a. pouch of water Striking the pack causes the pouch to break and the. temperature of the pack will either be raised or lowered depending on. whether the enthalpy of solution of the salt is negative or positive. Generally calcium chloride or magnesium sulfate is used in hot packs. and ammonium nitrate in cold packs,By kind permission of First Aid Warehouse. The reactions are,CaCl2 s aq Ca2 aq 2Cl aq H soln 82 8 kJ mol 1.
NH4NO3 s aq NH4 aq NO3 aq H soln 26 2 kJ mol 1, Experiments show that the addition of 13 g calcium chloride to 100 cm3 water raises the temperature from 20 oC. to 40 oC Similarly when 30 g ammonium chloride is dissolved in 100 cm3 water at 20 oC the temperature will be. lowered to 0 oC A typical cold pack works for approximately 20 minutes. Adapted from Instant Cold and Hot Packs published in Chemistry 4th Edition by Raymond Chang. a Define enthalpy of solution 3, b Draw a Born Haber cycle for the dissolving of calcium chloride and use it to show the connection between. the enthalpy of solution of a salt the hydration enthalpies of its ions and the lattice enthalpy of the salt 5. c Explain why the enthalpy of solution for calcium chloride is negative while that for ammonium nitrate. is positive 2, d Show by calculation that the temperature rise for 13 g calcium chloride when added to 100 cm3 water. is consistent with the value quoted in the extract above Assume that the specific heat capacity of water. and calcium chloride solution is 4 18 J g 1 K 1 4, e Outline an experiment using standard laboratory apparatus to determine the enthalpy of solution of ammonium nitrate. What assumptions are made in calculating the result State the most likely sources of error in the experiment and how. they might be minimised 13,Quality of language 1,A2 Level TOPIC 28 Questionsheet 7.
SYNOPTIC QUESTION 7,Entropy and free energy, a i Use these values for standard entropy J K 1mol 1. HNO3 l 156 O2 g 205 H2O l 70, to calculate the standard entropy for nitrogen dioxide given that the standard entropy change for the reaction. 4 HNO3 l 2 H2O l 4NO2 g O2 g is 919 J K 1mol 1 4, ii Comment on the sign and magnitude of the reaction entropy change 2. b i Give two examples of types of change or chemical situation where this relationship applies. ii Why does this relationship apply to these changes and not to a chemical reaction 2. c For the reaction,Fe2O3 s 3H2 g 2Fe s 3H2O g, the standard enthalpy change 95 kJ mol 1 and the standard enthalpies. for each substance are J K 1mol 1,Fe2O3 s 90 H2 g 131 Fe s 27 H2O g 189.
i Calculate the standard entropy change for the reaction 2. ii Estimate the temperature at which this reaction becomes possible 3. d Match up these standard entropy values J K 1mol 1 with the substances in the table. 51 72 95 187 230,Ethane gas,Solid sodium chloride,Hydrogen chloride gas. Sodium metal,Solid ammonium chloride,A2 Level TOPIC 28 Questionsheet 8. SYNOPTIC QUESTION 8,Cell reactions and S E P,Volumetric analysis. Organic practical techniques, a A common example of a disposable alkaline battery employs the two half equations. ZnO s H2O l 2e Zn s 2OH aq E 1 25 volts,2MnO2 s H2O l 2e Mn2O3 s 2OH aq E x volts.
i Combine these two half equations to produce an overall equation for the reaction. ii If the cell potential is 1 54 volts what is the value of x for the potential of the second half equation. iii State and explain which reaction takes place at the positive pole of the cell. iv What are the oxidation states of manganese in the two manganese oxides shown in the second. half equation 8, b Manganese occurs as MnO2 in the mineral pyrolusite A 2 00 g sample of this mineral was dissolved in acid and the. manganese content converted into manganate VII ions The manganate VII ions were extracted from the reaction. mixture and transferred to a 250 cm3 volumetric flask and made up to the mark with distilled water 25 cm3 of this. solution were removed by pipette and added to a conical flask containing 25 cm3 of 0 10 mol dm 3 Fe2 solution and. excess dilute sulfuric acid, The excess Fe2 in this reaction mixture was back titrated with 0 02 mol dm 3 potassium manganate VII solution After. several repetitions the average volume of 0 02 mol dm 3 potassium manganate VII solution required was 7 00 cm3. MnO4 aq 8H aq 5e Mn2 aq 4H2O l,Fe2 aq Fe3 aq e, Use this data to find the percentage of manganese in the 2 00 g sample by calculating the following. i Moles of MnO4 aq in 7 00 cm3 of 0 02 M potassium manganate VII solution. ii Moles of excess Fe2 aq, iii Hence moles of Fe2 aq that reacted with the manganate VII ions produced from the original sample. iv Moles of manganate VII ions produced from the original sample. v Moles of manganese in the original sample,vi Mass of manganese in the original sample.
vii Percentage of manganese in the original sample 8. c An alkaline solution of potassium manganate VII is useful as a powerful oxidising agent in the field of organic. chemistry for example benzenecarboxylic acid can be formed by the oxidation of methylbenzene In practice the. methylbenzene and alkaline potassium manganate VII are heated under reflux for some time and then allowed to. cool After filtration to remove insoluble residues the filtrate is treated with excess hydrochloric acid to release the. slightly soluble benzenecarboxylic acid from its soluble sodium salt The acid is then removed by filtration under. reduced pressure and purified by recrystallisation from hot water. i Sketch and label a diagram of the apparatus that is used for either carrying out the refluxing or filtration. under reduced pressure, ii How would you check that the recrystallised benzenecarboxylic acid was pure 5. A2 Level TOPIC 28 Questionsheet 9,SYNOPTIC QUESTION 9. Involving organic syntheses reaction mechanisms and yield calculation. Carefully read the following instructions for the preparation of 4 nitromethylbenzene. Carry out this experiment in a fume cupboard, Place concentrated nitric acid 14 cm3 into a flask and slowly add concentrated. sulfuric acid 18 cm3 During the addition gently swirl the flask and cool it under a. running cold water tap When the addition is complete further cool the flask in a. beaker of ice water until the temperature of its contents is below 10 oC At this stage. add methylbenzene 15 cm3 dropwise ensuring that the temperature does not rise. above 15 oC Fit a reflux condenser to the flask and place it in a beaker of water at. room temperature Gently swirl the flask and its contents for about 40 minutes organic layer. Transfer the mixture to a separating funnel and leave to settle Remove and discard aqueous layer. the lower layer Add 25 cm3 of water shake and then run off the lower layer Repeat. this once more with water then with aqueous sodium carbonate 1 mol dm 3 and. finally with water Pour the organic layer into a small conical flask containing a few. pieces of anhydrous calcium chloride Stopper the flask and leave for one hour. Decant the liquid into a distillation flask fitted with an air condenser Distil the liquid. and collect the fraction boiling between 236 240 oC. a Following the above procedure 15 cm3 of methylbenzene density 0 87 g cm 3 produced 11 5 g of. 4 nitromethylbenzene Calculate the percentage yield 3. b Explain using a balanced equation the function of the sulfuric acid in this reaction 3. c Name and outline the mechanism by which the conversion of methylbenzene into 4 nitromethylbenzene. d Why is the temperature not allowed to rise above 15 oC when the methylbenzene is being added 1. e Why is the product washed with water and with aqueous sodium carbonate 1. f During the final distillation why is an air condenser used rather than a water cooled condenser 2. g Suggest two further essential safety precautions that should be taken when carrying out this reaction 1. h Suggest two reasons why the yield is low 2, i If two further synthetic steps are carried out the 4 nitromethylbenzene can be converted into. 4 aminobenzenecarboxylic acid,Step 1 Step 2,Substance X.
Identify substance X in the above sequence of reactions and state the conditions and reagents required for. Step 1 and Step 2 5, j 4 Aminobenzenecarboxylic acid occurs naturally in many plants as a compound of folic acid What environmental. and economic factors should be considered when deciding whether to manufacture the product from methylbenzene. which is derived from crude oil or by extraction from plant tissue. A2 Level TOPIC 28 Questionsheet 10,SYNOPTIC QUESTION 10. The Haber Process,Chemical equilibrium,Redox and oxidation number. a This is a flow diagram for The Haber Process Give values identities for A E. Natural gas and water A C atm,Converter D oC Ammonia. Liquified air B,E catalyst, b Suggest the environmental considerations needed in both the siting and running of the plant 4.
c Ammonia is converted to nitric acid in three stages. Stage 1 Conversion to nitrogen oxide by reaction with oxygen at 900 oC in the presence of a platinum rhodium. Stage 2 Reaction of nitrogen oxide with oxygen at 200 oC to give nitrogen dioxide. Stage 3 Formation of nitric acid by dissolving nitrogen dioxide in water in the presence of oxygen. i Write an equation for each of these three stages. ii Give the initial and final oxidation states for nitrogen for each stage. iii In redox terms what has happened to nitrogen in all these reactions and why 8. i does not require heating once the process has started 2. ii operates at high temperature with a catalyst 1,What do these points suggest in each case. e The reaction in Stage 2 is found in which process and causes what environmental problem 2. f If Stage 1 was allowed to reach equilibrium a closed system would be needed What does this mean 1. g How does the use of a catalyst affect the position of equilibrium and why 2. A2 Level TOPIC 28 Questionsheet 11,SYNOPTIC QUESTION 11. Redox reactions half equations,Molecular geometry,Group trends. Volumetric analysis, Arsenic is a toxic element and there are many cases of it being used by murderers It is regularly monitored in European. public drinking water supplies The maximum allowable concentration in surface waters used for drinking water. abstraction is 0 01 milligrams per litre, Modern analytical methods used in water quality assurance begin with complete oxidation of arsenic in the sample.
with sodium persulfate and concentrated sulfuric acid to form H3AsO4 This is then reduced in two stages first using. potassium iodide tin II chloride and acid to form HAsO2 and second using aluminium powder and acid to form. arsenic III hydride AsH3, a Express the maximum allowable concentration of arsenic given above in mol dm 3 2. b What is the oxidation number of arsenic in each of the following compounds. iii AsH3 3,c Give half equations for these aqueous reactions. i AsH3 to H3AsO4 2,ii Iodide ion to iodine 1, d i Construct an equation for AsH3 reacting with iodine to form H3AsO4 and iodide ion 2. ii Calculate the volume of iodine solution containing 0 10 g dm 3 needed to exactly react with 1 dm3 solution. originally containing 0 05g arsenic and treated as above 7. iii State and explain which of the reactants in i is oxidised 2. e Draw a labelled diagram to describe the geometry of the AsH3 molecule 2. f Explain why in comparison to ammonia AsH3,i is a weaker base 3. ii has a smaller bond angle 3,A2 Level TOPIC 28 Questionsheet 12.
SYNOPTIC QUESTION 12,Types of isomerism,Pharmaceutical stereospecificity. a Define the term isomerism 2,b Consider these four compounds. A CH3COCH2CH3 B CH3CH2CH2CHO C CH3 2CHCHO D CH3CH CHCH3. i Name each compound 4,ii Which pair are chain isomers 1. iii Give a pair that are functional group isomers 1. iv Which compound could exist as E Z isomers Draw a diagram of each form labeling them E or Z 4. v Give the structural formula and name of a chain isomer of D 2. c What type of isomerism considers different arrangements in space for the same molecular structure 1. d Limonene is an essential oil found in citrus friut Its formula is as follows. i Copy out this formula and mark on it the structural feature which is responsible for the fact that limonene. exhibits optical isomerism 1, ii Write down the formula of the compound which would be formed if limonene were to be reacted with excess. hydrogen in the presence of a nickel catalyst Explain whether or not this new compound would exhibit. optical isomerism, iii One optical isomer of limonene is the ingredient of lemons which gives this fruit its characteristic taste.
Another optical isomer tastes of oranges Suggest the reason for this difference in taste. e Many commercially available drugs are optically active materials with one or more chiral centres Drugs from. natural sources are often single isomers but those synthesised in the laboratory are usually racemic mixtures of both. isomers With few exceptions these are marketed as racemic mixtures because of the expense and difficulty of. separating them Some pairs of isomers may have the same physiological activity but others may be very different. to the extent that one may be beneficial while the other could have disastrous side effects. i What steps should drug manufacturers take to ensure the safety of their product before putting it into general. ii In what way does a racemic mixture differ from each optical form and why 2. A2 Level TOPIC 28 Questionsheet 13,SYNOPTIC QUESTION 13. Fuels their depletion,Calculations for fuel yield, The following table provides generalised information on oil reserves and the rate of use in millions of tonnes from the. late nineteen eighties,Region Total reserves Annual rate of Annual rate. domestic consumption of production,Asia 6 000 650 300. Australasia 200 36 27,Middle East 90 000 150 800,Former USSR 8 000 400 500.
Central Europe 200 70 15,Western Europe 2 000 650 250. West Africa 8 000 100 350,North Africa 5 500 800 450. South Africa 17 000 250 3500, a If oil is produced at the rates shown which region will run out of oil first and after how many years 3. b If that region did not export oil how long would its supplies last 1. c Which region would run out of oil first if it only used its own resources and how long would this take 2. d Calculate the date when the world would run out of oil if these data are correct and the rates of. consumption and production are maintained 4, e Give reasons why the answer you gave in d is unlikely to be realistic 4. Coal resources are more extensive than oil resources and in times of embargo certain countries have produced oil. from coal At the beginning of the 20th century large quantities of coal were processed This resulted in one tonne of. coal yielding 340 m3 of coal gas as well as coke tar ammonia and sulfur. f i Suggest industrial applications for the products other than coal gas and tar obtained by heating coal 3. ii The tar produced can be used in road surfacing Which fraction from crude oil processing is also used for this. g Composition of typical coal gas by volume,Enthalpy of combustion kJ mol 1.
Hydrogen 50 285 8,Methane 30 890 0,Ethene 3 1411 0. Carbon monoxide 7 280 3,Carbon dioxide nitrogen and oxygen 10. Use the data above to calculate the energy produced from the complete combustion of 1 m3 of coal gas 3. h Renewable organic fuels are possible alternatives to hydrocarbon fuels Suggest two possible sources 2. i Give two reasons why hydrogen fuel cells are an environmentally advantageous alternative to hydrocarbon fuels 2.


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