1 This diagram represents the energy change that occurs when a d electron in a transition metal ion is excited by visible light.

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1 1 This igrm represents the energy hnge tht ours when eletron in trnsition metl ion is exite y visile light. Give the eqution tht reltes the energy hnge ΔE to the Plnk onstnt, h, n the frequeny, v, of the visile light. Use this eqution n the informtion in the igrm to lulte vlue for the frequeny of the visile light, n stte the units. The Plnk onstnt h J s. Eqution Clultion Explin why this eletron trnsition uses solution ontining the trnsition metl ion to e oloure. The energy hnge shown in the igrm represents the energy of re light n les to solution tht ppers lue. Blue light hs higher frequeny thn re light. Suggest whether the energy hnge ΔE will e igger, smller, or the sme for trnsition metl ion tht forms re solution. Explin your nswer. Energy hnge Explntion Stte three ifferent fetures of trnsition metl omplexes tht use hnge in the vlue of ΔE, the energy hnge etween the groun stte n the exite stte of the eletrons. Feture 1 Feture 2 Feture 3 (3 mrks) AQA Chemistry, 2013, Unit 5 (Question 6) Oxfor University Press This resoure sheet my hve een hnge from the originl 1

2 2 Trnsition metl ompouns hve rnge of pplitions s tlysts. Stte the generl property of trnsition metls tht llows the vnium in vnium(v) oxie to t s tlyst in the Contt Proess. Write two equtions to show how vnium(v) oxie ts s tlyst in the Contt proess. Eqution 1 Eqution 2 In the Contt Proess, vnium(v) oxie ts s heterogeneous tlyst. i Give the mening of the term heterogeneous. Give one reson why impurities in the retnts n use prolems in proesses tht use heterogeneous tlysts. The oxition of CO 2 4 ions y MnO4 ions in solution is n exmple of retion tht is utotlyse. i Give the mening of the term utotlyse. Ientify the utotlyst in this retion. i Write two equtions to show how the utotlyst is involve in this oxition of CO ions. 2 4 Eqution 1 Eqution 2 AQA Chemistry, 2013, Unit 5 (Question 6) Oxfor University Press This resoure sheet my hve een hnge from the originl 2

3 3 Soli iron(ii) ethneiote ihyrte (FeC 2 O 4.2H 2 O) hs polymeri struture. Two repeting units in the polymer hin re shown. Eh iron ion is lso one to two wter moleules. These re not shown in the igrm. Nme the type of on tht is represente y the rrows. In terms of eletrons explin how the wter moleules, not shown in the igrm, form ons to the iron. Preit the vlue of the on ngle etween the two ons to iron tht re forme y these two wter moleules. Iron(II) ethneiote ihyrte n e nlyse y titrtion using potssium mngnte(vii) in solution. In this retion, mngnte(vii) ions oxse iron(ii) ions n ethneiote ions. A g smple of impure FeC 2 O 4.2H 2 O ws issolve in n exess of ilute sulfuri i n me up to 250 m 3 of solution m 3 of this solution eolourise m 3 of mol m 3 solution of potssium mngnte(vii). i Use the hlf-equtions given elow to lulte the reting rtio of moles of mngnte(vii) ions to moles of iron(ii) ethneiote. MnO 4 8H 5e Mn 4H 2 O Fe Fe 3 e CO 2 4 2CO 2 2e Clulte the perentge y mss of FeC 2 O 4.2H 2 O in the originl smple. (5 mrks) AQA Chemistry, 2012, Unit 5 (Question 6) Oxfor University Press This resoure sheet my hve een hnge from the originl 3

4 4 Give one exmple of ientte lign. Give one exmple of liner omplex ion forme y trnsition metl. Write n eqution for sustitution retion in whih the omplete replement of ligns in omplex ion ours with hnge in oth the o-orintion numer n the overll hrge of the omplex ion. Write n eqution for sustitution retion in whih the omplete replement of ligns in omplex ion ours without hnge in either the o-orintion numer or the overll hrge of the omplex ion. e When solution ontining [Co(H 2 O) 6 ] ions is trete with solution ontining EDTA 4 ions, more stle omplex is forme. Write n eqution for this retion n explin why the omplex is more stle. Eqution Explntion (3 mrks) AQA Chemistry, 2003, Unit 5 (Question 5) 5 Trnsition metl ions n t s homogeneous tlysts in reox retions. For exmple, iron(ii) ions tlyse the retion etween peroxoisulfte (S2O 8 ) ions n ioie ions. Stte the mening of the term homogeneous. Suggest why ions from s lok elements o not usully t s tlysts. Oxfor University Press This resoure sheet my hve een hnge from the originl 4

5 Write n eqution for the overll retion tht ours, in queous solution, etween SO ions n I ions. Give one reson why, in the sene of tlyst, the tivtion energy for the retion etween SO ions n I ions is high. e Write two equtions to show how Fe ions n tlyse the retion etween SO ions n I ions. Suggest one reson why the tivtion energy for eh of these retions is low. Eqution 1 Eqution 2 Reson (3 mrks) f Explin why Fe 3 ions re s effetive s Fe ions in tlysing this retion. AQA Chemistry, 2010, Unit 5 (Question 3) Oxfor University Press This resoure sheet my hve een hnge from the originl 5