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Transcription of this question: 6.Copper forms two chlorides, copper(l) chloride and copper(ll) chloride.(ii)(iii)State the electron configuration of the ion.Copper(ll) chloride is used as a catalyst in the production of chlorine fromhydrogen chloride.4HCl (g) + (g) 2C12(g) + 2H20(g)Calculate the standard enthalpy change, AHO, in kJ, for this reaction, usingsection 12 of the data booklet.The diagram shows the Maxwell—Boltzmann distribution and potential energyprofile for the reaction without a catalyst.Annotate both charts to show the activation energy for the catalysed reaction,using the label Ea[2][2]2eKinetic energy4HCl (g) + 02(g)2C12 (g) + (g)Progress of reaction(iv)Explain how the catalyst increases the rate of the reaction.[2](b)Solid copper(ll) chloride absorbs moisture from the atmosphere to form a hydrate offormula CuC12•xH20.A student heated a sample of hydrated copper(ll) chloride, in order to determine thevalue of x. The following results were obtained:Mass of crucible = 16.221 gInitial mass of crucible and hydrated copper(ll) chloride = 18.360gFinal mass of crucible and anhydrous copper(ll) chloride = 17.917 gDetermine the value of x.(c)Two electrolysis cells were assembled using graphite electrodes and connected inseries as shown.Molten copper(l) chlorideDilute aqueous copper(ll) chloride0)State how current is conducted through the wires and through the electrolyte.[2]Wires:Electrolyte:(ii)Write the half-equation for the formation of gas bubbles at electrode 1.(iii) Bubbles of gas were also observed at another electrode. Identify the electrodeand the gas.Electrode number (on diagram):Name of gas:(iv)Deduce the half-equation for the formation of the gas identified in (c)(iii).(d)Determine the enthalpy of solution of copper(ll) chloride, using data from sections 18and 20 of the data booklet.The enthalpy of hydration of the copper(ll) ion is —2161 kJ mol-l[2]Copper(l) chloride undergoes a disproportionation reaction, producing copper(ll)chloride and copper.0)(ii)(iii)2Cu* (aq) —Y Cu (s) + Cu2+ (aq)Calculate the cell potential at 298K for the disproportionation reaction, in V, usingsection 24 of the data booklet.Comment on the spontaneity of the disproportionation reaction at 298 K.Calculate the standard Gibbs free energy change, AGO, to two significant figures,for the disproportionation at 298K. Use your answer from (e)(i) and sections 1and 2 of the data booklet.(iv) Suggest, giving a reason, whether the entropy of the system increases ordecreases during the disproportionation.(v)Deduce, giving a reason, the sign of the standard enthalpy change, AHO, for thedisproportionation reaction at 298 K.Predict, giving a reason, the effect of increasing temperature on the stability ofcopper(l) chloride solution.(f)Dilute copper(ll) chloride solution is light blue, while copper(l) chloride solution is colourless.(i) Describe how the blue colour is produced in the Cu(ll) solution. Refer to section 17of the data booklet.(ii) Deduce why the Cu(l) solution is colourless.(iii)When excess ammonia is added to copper(ll) chloride solution, the dark bluecomplex ion, forms.State the molecular geometry of this complex ion, and the bond angles within it.Molecular geometry:Bond angles:(iv)Examine the relationship between the Brønsted—Lowry and Lewis definitions of abase, referring to the ligands in the complex ion [CUC14]2-.[2]

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