Answer all questions in the spaces provided. 1 (a) (i) State what is meant by partition coefficient. ................................................................................................................................. ….............................................................................................................................. ............................................................................................................................. [1] Ammonia is soluble in both water and organic solvents. An aqueous solution of ammonia is shaken with the immiscible trichloromethane. The mixture is left to reach equilibrium. Samples are taken from each layer and titrated with dilute hydrochloric acid. • A 25.0 cm3 sample from the trichloromethane layer requires 13.0 cm3 of 0.100 mol dm-3 HCl to reach end-point. • A 10.0 cm3 sample from the aqueous layer requires 12.5 cm3 of 0.100 mol dm-3 HCl to reach end-point. (ii) Calculate the partition coefficient, Kpartition, of ammonia between trichloromethane and water. Kpartition = .............................. [2] (ii) Butylamine, C4H9NH2, is also soluble in both water and organic solvents. Suggest how the value of Kpartition of butylamine between trichloromethane and water would compare to the value of Kpartition calculated in (ii). Explain. ................................................................................................................................. ….............................................................................................................................. ............................................................................................................................. [2] 2 (b) (i) Explain why butylamine is basic. ................................................................................................................................. ….............................................................................................................................. ............................................................................................................................. [1] (ii) Write an equation to show butylamine reacting as a base. ............................................................................................................................. [1] (iii) State how the basicity of butanamide compares to that of butylamine. ............................................................................................................................. [1] (iv) State a reagent for the conversion of butanamide into butylamine. ............................................................................................................................. [1] [Total: 9] 3 2 An electrochemical cell is constructed using two half cells: Sn4+/Sn2+ and Al3+/Al. (a) State the material used for the electrode in each half-cell. Sn4+/Sn2+ half-cell …..................................................................................................... Al3+/Al half-cell .............................................................................................................. [1] (b) The cell is operated at 298 K. The Al3+/Al half-cell has standard concentrations. The Sn4+/Sn2+ half-cell has [Sn4+] = 0.300 mol dm-3 and [Sn2+] = 0.150 mol dm-3. (i) Use the Nernst equation to calculate the electrode potential, E, of the Sn4+/Sn2+ half-cell under these conditions. E = .............................. V [2] (ii) Calculate the Ecell under these conditions. Ecell = .............................. V [1] (iii) Write an equation for the overall reaction that occurs ............................................................................................................................. [2] 4 (c) Aluminium is produced industrially by electrolysis of a melt containing large amounts of Al3+ ions. Calculate the mass of aluminium that is obtained when a current of 300 000 A is passed for 24 hours. Give your answer to three significant figures. mass = .............................. units = .............................. [4] (d) Explain why chromium metal cannot be obtained by the electrolysis of dilute aqueous chromium(II) sulfate. Your answer should include data from the Data Booklet. ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... ................................................................................................................................. [2] [Total: 12] 5 3 Thermodynamics can be used to assess the feasibility of a process. (a) The table below lists equations for five processes. For each process, predict the sign of DS. sign of DS process NaBr(s) + (aq) ® NaBr(aq) H2O(l) ® H2O(g) 2H2(g) + O2(g) ® 2H2O (g) CoCl2(s) + 6H2O(l) ® CoCl2.6H2O(s) [2] (b) Ethanol can be combusted as shown in the equation. CH3CH2OH(l) + 3O2(g) ® 2CO2(g) + 3H2O(l) Standard entropies are shown below in the table. substance CH3CH2OH(l) O2(g) CO2(g) H2O(l) Sq, J K-1 mol-1 161 205 214 70 Calculate the standard entropy change, DSq, for this reaction. DSq = .............................. J K-1 mol-1 [2] (c) The combustion of ethanol is an exothermic reaction. This reaction occurs spontaneously at low temperature but does not occur at high temperature. Explain why. ...................................................................................................................................... ...................................................................................................................................... ................................................................................................................................. [2] 6 (d) The decomposition of calcium carbonate is an endothermic reaction. CaCO3(s) ® CaO(s) + CO2(g) DH = +178 kJ mol-1 and DS = +159 J K-1 mol-1 Calculate the minimum temperature at which this reaction becomes feasible. Show all your working. [3] [Total: 9] 7 4 Much of the preparation of evidence to solve crimes relies on instrumental analysis. This question deals with some of the techniques used. (a) Electrophoresis can be used to separate amino acids produced by hydrolysis of proteins. The amino acids are placed in a buffered solution in an electric field. In a solution of given pH, what two factors affect the movement of a given amino acid? (i) ............................................................................................................................ [1] (ii) ............................................................................................................................ [1] (b) NMR and mass spectrometry are also used in detection of certain molecules, particularly those containing hydrogen atoms. (i) Explain how and why the NMR spectrum of propanal, CH3CH2CHO, would be different from that of propanone, CH3COCH3, which contains the same atoms. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ............................................................................................................................ [2] (ii) Explain how and why the mass spectrum of the two compounds in (i) would be different. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ............................................................................................................................ [2] 8 (c) At one time, bromomethane, CH3Br, was widely used to control pests in agriculture. It is now known to break down in the stratosphere and contribute to the destruction of the ozone layer. Samples can be screened for traces of bromomethane by subjecting them to mass spectrometry. (i) Which peak(s) would show the presence of bromine in the compound? ............................................................................................................................ [1] (ii) How could you tell by studying the M and M+2 peaks that the compound contained bromine rather than chlorine? ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ............................................................................................................................ [2] [Total: 9] 9 10 10 5 The initial reaction rate for propanone and iodine in acid solution is measured in aLQ series KHLQLWLDO LQLWLDO UDWHRI RI UHDFWLRQ IRUSURSDQRQH SURSDQRQH DQG LRGLQH LQDFLG DFLG VROXWLRQ LVPHDVXUHG PHDVXUHG DVHULHV VHULHVRI RI 10LRGLQH 44 77KH UDWH UHDFWLRQ IRU DQG LQ VROXWLRQ LV LQ D experiments at a constant temperature. of experiments constanttemperature. temperature. experiments at at aa constant 4 KH LQLWLDO UDWH RI UHDFWLRQ IRU SURSDQRQH DQG LRGLQH LQ DFLG VROXWLRQ LV PHDVXUHG LQ D VHULHV RI 7 catalyst experiments at a constant temperature. ++++catalyst &+ &2&+ + I &+ &2&+ I+I &+33&2&+33 + I22 &+33&2&+22I+I ++ catalyst 7 KHUDWHHTXDWLRQZDVGHWHUPLQHGH[SHULPHQWDOO\WREHDVVKRZQ &+ &2&+ + I &2&+2I+I The rate equation was experimentally determined as&+ the 3following. 3 3 2 7KHUDWHHTXDWLRQZDVGHWHUPLQHGH[SHULPHQWDOO\WREHDVVKRZQ rate = k>&+ &2&+ @>+ ] 7KHUDWHHTXDWLRQZDVGHWHUPLQHGH[SHULPHQWDOO\WREHDVVKRZQ rate = k>&+ 3&2&+ 3@>++] + 3 3 (a) 6WDWHWKHRUGHURIUHDFWLRQZLWKUHVSHFWWR rate = k>&+3&2&+3@>++] (a) 6WDWHWKHRUGHURIUHDFWLRQZLWKUHVSHFWWR (a) State the order of reaction with respect to Ɣ &+ &2&+ .......................................................................................................................... 6 3 3 ƔWDWHWKHRUGHURIUHDFWLRQZLWKUHVSHFWWR &+3&2&+ •(a) CH 3COCH 3 ............................................................................................................ 3 .......................................................................................................................... • Ɣ &+ I 3......................................................................................................................................... &2&+3 .......................................................................................................................... I2Ɣ Ɣ ............................................................................................................................ I 2 ......................................................................................................................................... • + + HƔƔ …......................................................................................................................... ........................................................................................................................................ I++ ......................................................................................................................................... + DQGVWDWHWKHRYHUDOORUGHURIWKLVUHDFWLRQ ............................................................................... and Ɣ the overall order of this reaction is …..................................................................... ........................................................................................................................................ + –2 •(b) the concentration of I2 is 1.25 x 10 10–33-2is mol dm –3 –1 1.50 u s-3 10 mol dm–3–3 Ɣ WKHFRQFHQWUDWLRQRI&+ 3&2&+ mol dm 7 KHUDWHRIWKLVUHDFWLRQLVu –2when &2&+ is 1.50 u 10 Ɣ W KHFRQFHQWUDWLRQRI&+ –2 –3 mol dm + -1 -3 3 3 Ɣ concentration WKHFRQFHQWUDWLRQRII is 1.25 u 10–2mol moldm dm–3. • the of H is 27.75 x 10 2 Ɣ +2 ........................................................................................................................................ DQGVWDWHWKHRYHUDOORUGHURIWKLVUHDFWLRQ ............................................................................... [2] [2] [2] DQGVWDWHWKHRYHUDOORUGHURIWKLVUHDFWLRQ ............................................................................... [2] -3 -3 -1 (b) The of this reaction is 5.40 x 1010 mol –3 moldm dm–3–3ss–1–1 when when (b) rate 7KHUDWHRIWKLVUHDFWLRQLVu –3 mol dm whendm-3 7KHUDWHRIWKLVUHDFWLRQLVu •(b) the concentration of CH3COCH310 is 1.50 x 10s-2 mol Ɣ KHFRQFHQWUDWLRQRII dm + 1.25 u 10 –1 –3 2 is –3 Ɣ WWKHFRQFHQWUDWLRQRI&+ WKHFRQFHQWUDWLRQRI+ is 7.75 u 10–1mol mol dm–2 . u dm 10 Ɣ + 3&2&+3 is 1.50 –3 mol dm Ɣ W KHFRQFHQWUDWLRQRI+ is 7.75 u 10 mol . State the unit of k. –2 reaction. –3 (i) Calculate the rate constant, k, for this Ɣ WKHFRQFHQWUDWLRQRII2 is 1.25 u 10 mol dm + (i) WKHFRQFHQWUDWLRQRI+ &DOFXODWHWKHUDWHFRQVWDQWkIRUWKLVUHDFWLRQ6WDWHWKHXQLWVRIk. Ɣ is 7.75 u 10–1 mol dm–3. (i) &DOFXODWHWKHUDWHFRQVWDQWkIRUWKLVUHDFWLRQ6WDWHWKHXQLWVRIk. (i) &DOFXODWHWKHUDWHFRQVWDQWkIRUWKLVUHDFWLRQ6WDWHWKHXQLWVRIk. k = .............................. k = .............................. units .............................. k = .............................. [1] k ===.............................. units .............................. [2] units = .............................. [1] [2] units = .............................. (ii) &RPSOHWHWKHWDEOHE\SODFLQJoneWLFN LQHDFKURZWRGHVFULEHWKHHIIHFWRIdecreasing [2] (ii) &WKHWHPSHUDWXUHRQWKHUDWHFRQVWDQWDQGRQWKHUDWHRIUHDFWLRQ RPSOHWHWKHWDEOHE\SODFLQJoneWLFN LQHDFKURZWRGHVFULEHWKHHIIHFWRIdecreasing (ii) Complete the table below by placing one tick (Ö) in each row to describe the WKHWHPSHUDWXUHRQWKHUDWHFRQVWDQWDQGRQWKHUDWHRIUHDFWLRQ (ii) &RPSOHWHWKHWDEOHE\SODFLQJoneWLFN LQHDFKURZWRGHVFULEHWKHHIIHFWRIdecreasing effectWKHWHPSHUDWXUHRQWKHUDWHFRQVWDQWDQGRQWKHUDWHRIUHDFWLRQ of decreasing temperature on the rate constant and theincreases rate of reaction. decreases QRFKDQJH decreases QRFKDQJH increases rate constant decreases QRFKDQJH increases rate constant UDWHRIUHDFWLRQ rate constant UDWHRIUHDFWLRQ [1] [1] UDWHRIUHDFWLRQ [1] [1] 10 11 )URPWKHUHVXOWVDJUDSKLVSURGXFHGZKLFKVKRZVKRZWKHFRQFHQWUDWLRQRII (c) (c) From the results, a graph is produced which shows how the concentration of I2 2FKDQJHVGXULQJ the reaction. changes during the reaction. 11 (c) )URPWKHUHVXOWVDJUDSKLVSURGXFHGZKLFKVKRZVKRZWKHFRQFHQWUDWLRQRII2FKDQJHVGXULQJ the reaction. [I2] [I2] 0 0 time 0 0 time Describe how this graph could be used to determine the initial rate of the reaction. 'HVFULEHKRZWKLVJUDSKFRXOGEHXVHGWRGHWHUPLQHWKHLQLWLDOUDWHRIWKHUHDFWLRQ 'HVFULEHKRZWKLVJUDSKFRXOGEHXVHGWRGHWHUPLQHWKHLQLWLDOUDWHRIWKHUHDFWLRQ ..................................................................................................................................... .................................................................................................................................................... .................................................................................................................................................... ..................................................................................................................................... .................................................................................................................................................... .................................................................................................................................................... ................................................................................................................................ [2] .............................................................................................................................................. [2] .............................................................................................................................................. [2] (d) On the axes below, sketch a graph to show how the initial rate changes with different (d) 2QWKHD[HVEHORZVNHWFKDJUDSKWRVKRZKRZWKHLQLWLDOUDWHFKDQJHVZLWKGLIIHUHQWLQLWLDO (d) 2QWKHD[HVEHORZVNHWFKDJUDSKWRVKRZKRZWKHLQLWLDOUDWHFKDQJHVZLWKGLIIHUHQWLQLWLDO initial concentration of CH3COCH in this reaction. in 3this reaction. FRQFHQWUDWLRQVRI&+ &2&+ FRQFHQWUDWLRQVRI&+ 3 3 3 in this reaction. 3&2&+ rate rate 0 0 0 [CH3COCH3] [1] 0 [1] [CH3COCH3] [1] © UCLES 2019 11 9701/42/M/J/19 [Turn over 12 (e) The rate of a reaction between metal ions was studied. The following three-step (e) 7KHUDWHRIDUHDFWLRQEHWZHHQPHWDOLRQVZDVVWXGLHG7KHIROORZLQJWKUHHVWHSPHFKDQLVP mechanism has been suggested. Step 1 is the rate-determining step. KDVEHHQVXJJHVWHGIRUWKLVUHDFWLRQ6WHSLVWKHUDWHGHWHUPLQLQJVWHS step 1 Ce4+0Q2+ Ce3+0Q3+ step 2 Ce4+0Q3+ Ce3+0Q4+ VWHS 0Q4+ + Tl + Tl 3+0Q2+ (i) ([SODLQWKHPHDQLQJRIWKHWHUPrate-determining step. (i) Explain the meaning of the term rate-determining step. ............................................................................................................................................. ……...................................................................................................................... ....................................................................................................................................... [1] ……................................................................................................................. [1] (ii) Use this mechanism to (ii) mechanism to Use this Ɣ GHWHUPLQHWKHRYHUDOOHTXDWLRQIRUWKLVUHDFWLRQ • determine the overall equation for this reaction ............................................................................................................................................. ……............................................................................................................. [1] • Ɣ VXJJHVWWKHUROHRI0Q2+ ions in this mechanism. Explain your answer. suggest the role of Mn2+ ions in this mechanism. Explain your answer. ............................................................................................................................................. ......................................................................................................................... ............................................................................................................................................. ......................................................................................................................... ............................................................................................................................................. ......................................................................................................................... .................................................................................................................... [1] [Total: 11] Topic: Kinetic Total= 13 +11 = 24 12 [2] [Total: 11] 6 A mixture of three compounds, J, K and L, was analysed by thin layer chromatography using a polar stationary phase and a non-polar mobile phase. The three compounds all have similar molecular masses. The resulting chromatogram is shown below. (a) Identify which spot corresponds to each compound. [2] (b) Explain your answers to (a). ...................................................................................................................................... ...................................................................................................................................... ................................................................................................................................ [2] Serotonin is converted by enzymes in the liver to compound M. 13 (c) By reference to the Data Booklet, suggest how the infra-red spectrum of M would differ from that of serotonin. ...................................................................................................................................... ...................................................................................................................................... ................................................................................................................................ [2] (d) The proton NMR spectrum of M dissolved in CDCl3 shows eight peaks due to the eight different types of proton present in the molecule. The proton NMR spectrum of M dissolved in D2O was recorded. Predict the number of peaks that would be seen in the proton NMR spectrum of M in D2O. Explain your answer. ...................................................................................................................................... ...................................................................................................................................... ................................................................................................................................ [2] (e) Compound M can be polymerized under certain conditions to form polymer N. Polymer N is biodegradable, unlike polyethene which is not. Explain why N is biodegradable. ...................................................................................................................................... ...................................................................................................................................... ................................................................................................................................ [2] [Total: 10] 14 12 12 7 Asparagine and and valine are two naturally occurring amino acids. 7 Asparagine Asparagine andvaline valine are naturally occurring amino 7 are twotwo naturally occurring amino acids.acids. O O O O O OH OH O OH OH NH2 NHNH 2 NH2 2 NH2 NH2 asparagine asparagine valine valine (a) (a) GiveGive the molecular formula of asparagine. Give the molecular formula ofof asparagine. (a) the molecular formula asparagine. .............................................................................................................................................. [1][1][1] ................................................................................................................................ .............................................................................................................................................. (b) (b) Name all ofall the groups in aninasparagine molecule. (b) Name of the groups an asparagine molecule. Name all offunctional thefunctional functional groups in an asparagine molecule. ................................................................................................................................ .............................................................................................................................................. [2][2][2] .............................................................................................................................................. (c) (c) Draw the structure of the dipeptide formed by valine asparagine. (c) Draw the ofof the dipeptide formed by valine and asparagine. Draw the structure structure the dipeptide formed byand valine and asparagine. The peptide bond should shown displayed and be clearly labelled. The The peptide bondbond should be shown displayed and and should beshould clearly labelled. peptide should bebe shown displayed should be clearly labelled. [2] [2] A solution of valine in water a buffer solution. (d) (d) A solution of valine in water acts acts as aas buffer solution. Explain is meant a buffer solution. (i) (i) Explain whatwhat is meant by aby buffer solution. [2] ............................................................................................................................................. ............................................................................................................................................. (d) A solution of valine in water acts as a buffer solution. (i) Explain what is meant by a buffer solution. ............................................................................................................................................. ............................................................................................................................................. ….............................................................................................................................. ....................................................................................................................................... ....................................................................................................................................... [2] [2] ….............................................................................................................................. H two equations to explain valine canas act a buffer. the formula H2NCHRCO (ii) (ii) WriteWrite two equations to explain how how valine can act a as buffer. Use Use the formula H2NCHRCO 2H 2 for valine in your equations. for ............................................................................................................................ valine in your equations. [2] ............................................................................................................................................. ............................................................................................................................................. 15 ............................................................................................................................................. ............................................................................................................................................. [2] [2] (ii) Write two equations to explain how valine can act as a buffer. Use the formula H2NCHRCO2H for valine in your equations. ….............................................................................................................................. .................................................................................................................................. [2] (e) Each valine molecule has one chiral carbon atom. Draw three-dimensional diagrams to show the two optical isomers of valine. The (CH3)2CH group can be represented as R. [2] (f) Asparagine is hydrolysed when heated with aqueous sulfuric acid. Write an equation for this reaction. ................................................................................................................................ [2] [Total: 13] 16 7 Phenylethanone importantchemical chemical with with many 8 4Phenylethanone is is ananimportant manyuses. uses. phenylethanone CH3 C O (a) Phenylethanone can be synthesised using benzene as one of the starting materials. (a) Phenylethanone can be synthesised using benzene as one of the starting materials. Identify the other reagents used and describe any essential reaction conditions. Identify the other reagents used and describe any essential reaction conditions. ...................................................................................................................................... .................................................................................................................................................... ................................................................................................................................. [2] .............................................................................................................................................. [2] (b) Phenylethanone is treated separately with three reagents. (b) Phenylethanone separately withformula three reagents. Complete the tableistotreated give the structural of one organic product formed and the Complete name of mechanism If there no the reaction, write ‘no reaction’. the table, forinvolved. each reagent, to is give structural formula of one organic product formed and the name of the mechanism involved. If there is no reaction you should write ‘no reaction’. reagent reagent organic product organic product name of mechanism name of mechanism chlorine gas at 10°C in the presence of qC UVinlight chlorine gas at 10 the presence of ultra-violet light a mixture of concentrated a mixture of concentrated nitric nitric and sulfuric and sulfuric acids atacids 50 qC at 50°C bromine water bromine water [5] 17 [5] 8 (c) Phenylethanone reacts with HCN in the presence of a small amount of NaCN. (c) Phenylethanone reacts with HCN in the presence of a small molecule NaCN. (i) 8 Name the mechanism of this reaction. (i) Name the mechanism of this reaction. (c) Phenylethanone reacts with HCN in the presence of a small amount of NaCN. ....................................................................................................................................... [1] ............................................................................................................................ [1] (ii) (i) Name the mechanism of this reaction. Draw the mechanism of this reaction below. Include all relevant charges, dipoles, lone pairs and curly arrows. Your mechanism should show the catalytic role of CN– ions. ....................................................................................................................................... [1] (ii) Draw the mechanism of this reaction. Include relevant charges,charges, dipoles,dipoles, lone lone (ii) Draw the mechanism of this reaction below.all Include all relevant phenylethanone intermediate product – pairs and curly arrows. Your mechanism should show the catalytic role of CN ions. pairs and curly arrows. Show the catalytic role of CN ions. phenylethanone CH3 intermediate product C O CH 3 C O [4][4] (d) Phenylethanone can be used as a starting material to make phenylethene in a two-step [4] synthesis. (d) Phenylethanone can be used as a starting material to make phenylethene in a twostep process. phenylethene (d) Phenylethanone can be used as a starting material to make phenylethene in a two-step phenylethanone D synthesis. H H CH3 step 1 step 2 C phenylethene C C phenylethanone D H H H O CH 3 step 1 step 2 C C C H (i) Draw theOstructure of compound D in the box. [1] (i) Draw the structure of compound D in the box above. (ii) [1] Identify a suitable reagent for step 1. (i) Draw the structure of compound ....................................................................................................................................... [1] [1] (ii) Identify a suitable reagent for step 1.D in the box. (ii) Identify a suitable reagent for step (iii)............................................................................................................................. Identify a suitable reagent for step 2. 1. [1] ....................................................................................................................................... ....................................................................................................................................... [1] [1] (iii) Identify a suitable reagent for step 2. (iii) Identify a suitable reagent for step 2. ............................................................................................................................. [1] ....................................................................................................................................... [1] 18 (iv) State the number of peaks in the C-13 NMR spectrum of phenylethene. ............................................................................................................................. [1] (v) Suggest C-13 chemical shift ranges expected for the different types of carbon environment in phenylethanone. ….............................................................................................................................. ….............................................................................................................................. ….............................................................................................................................. ............................................................................................................................ [2] [Total: 18] 19 9 (a) Sketch the shape of a d orbital. Draft Prelim 2020, JC2 Chemistry 3 6 (a) 6NHWFKWKHVKDSHRIDGRUELWDO [1] (b) Some elements with d orbital can be classified as transition elements. (i) Briefly explain the term transition element. [1] .................................................................................................................................. (b) (i) ([SODLQZKDWLVPHDQWE\WKHWHUPtransition element. ............................................................................................................................. [1] ............................................................................................................................................. ....................................................................................................................................... [1] Transition elements can form complex ions which contain ligands. 7UDQVLWLRQHOHPHQWVFDQIRUPFRPSOH[LRQVZKLFKFRQWDLQOLJDQGV (ii) Name the type of bonding that occurs between a ligand and a transition element. (ii) 1DPHWKHtype of bondingWKDWRFFXUVEHWZHHQDOLJDQGDQGDWUDQVLWLRQHOHPHQW ............................................................................................................................. [1] ....................................................................................................................................... [1] (c) Give the formulae of two oxides of iron. State the oxidation number of iron in each (c) *LYHWKHIRUPXODHRIWZRR[LGHVRILURQ6WDWHWKHR[LGDWLRQQXPEHURILURQLQHDFKFRPSRXQG compound. ..................................................................................................................................... .................................................................................................................................................... ................................................................................................................................[1] [1] .............................................................................................................................................. (d) &2DQG&1–DUHPRQRGHQWDWHOLJDQGV - (d) CO and CN are monodentante ligands. &RPSOHWHWKHWDEOHIRUWKHIROORZLQJWZRFRPSOH[HV Complete the table below for the following two complexes. metal ion OLJDQG co-ordination QXPEHU 1L2+ CO 4 Fe3+ &1– IRUPXODRI complex ion FKDUJHRI complex ion 3[2] [2] 20 7 (e) Transition element complexes can exhibit stereoisomerism. [Cu(H2O)4(NH3)2]2+ and (e) 7UDQVLWLRQHOHPHQWFRPSOH[HVFDQH[KLELWVWHUHRLVRPHULVP>&X +2O)4 1+3)2]2+DQG3W 1+3)2Cl 2 Pt(NH 2Cl2 show the same type of isomerism. show the3)sameW\SHRILVRPHULVP (i) Name this type of isomerism. (i) 1DPHWKLVW\SHRILVRPHULVP ............................................................................................................................ [1] ....................................................................................................................................... [1] (ii)(ii)&Complete RPSOHWHWKHWKUHHGLPHQVLRQDOGLDJUDPVRIWKHWZRLVRPHUVIRU>&X +2O)4 1+3)2]2+ and the diagrams below for the Cu and Pt complexes. 3W 1+3)2Cl 2. Cu Cu Pt Pt [2] [2] [Total: 9] END OF PAPER 21