Edexcel Jan 2017 (IAL) Paper 2 Q20

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20 The effect of changing conditions on a system at equilibrium can be illustrated by the reaction involving ICl and ICl3 which may be studied using the apparatus shown. conc HCl to fume cupboard (or open window) screw clip screw clip to filter pump 3 way tap I2 KMnO4 place where ICl and ICl3 are formed NaOH(aq) The equilibrium is ICl(l) + Cl2(g) (cid:85)(cid:1)(cid:1)(cid:1)(cid:1)ICl3(s) (cid:507)H = 105.9 kJ mol1 brown pale green yellow (a) Explain the effect of increasing the amount of chlorine on the system at equilibrium. State what you would see. (2)(b) Explain the effect of placing the U-tube in a beaker of warm water on the system at equilibrium. State what you would see. (2)18 *P48368A01824* D O N O T W R I T E I N T H I S A R E A D O N O T W R I T E I N T H I S A R E A D O N O T W R I T E I N T H I S A R E A<br /> A E R A S I H T N I E T I R W T O N O D (c) The chlorine gas is generated in the apparatus by the reaction between concentrated hydrochloric acid and potassium manganate(VII). 16H+ + 10Cl + 2MnO4(cid:111) 5Cl2 + 2Mn2+ + 8H2O Show by the use of all relevant oxidation numbers that this is a redox reaction. (2)(d) Suggest the purpose of the sodium hydroxide solution in the flask on the right hand side of the apparatus. (1) A E R A S I H T N I E T I R W T O N O D(Total for Question 20 = 7 marks) TOTAL FOR SECTION B = 39 MARKS A E R A S I H T N I E T I R W T O N O D *P48368A01924* 19 Turn over<br />

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