Edexcel Jun 2017 (IAL) Paper 1 Q10

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10 Calcium chloride can be prepared by reacting calcium carbonate with dilute hydrochloric acid. CaCO3(s) + 2HCl(aq) (cid:111) CaCl2(aq) + H2O(l) + CO2(g) (a) The ionic equation for the reaction is Ca2+(s) + 2Cl(aq) (cid:111) CaCl2(aq) CaCO3(s) + 2H+(aq) (cid:111) Ca2+(aq) + H2O(l) + CO2(g) CO3 2(s) + 2H+(aq) (cid:111) H2O(l) + CO2(g) D CaCO3(s) + 2H+(aq) + 2Cl(aq) (cid:111) CaCl2(aq) + H2O(l) + CO2(g) (1) (b) An excess of calcium carbonate is used in the preparation. The sequence of processes needed to obtain crystals of calcium chloride from the reaction mixture is (1) filtering, concentrating the solution, slowly evaporating. filtering, slowly evaporating, distilling. C concentrating the solution, filtering, distilling. D concentrating the solution, slowly evaporating, filtering. (c) The excess calcium carbonate was added to 100 cm3 of 2.00 mol dm3 hydrochloric acid. The mass of calcium chloride crystals obtained was 10.4 g. Molar mass of calcium chloride crystals, CaCl2.2H2O = 147 g mol1. The percentage yield, by mass, of calcium chloride crystals is (1) A 71.2 B 70.7 C 35.4 D 17.7 Use this space for any rough working. Anything you write in this space will gain no credit. (Total for Question 10 = 3 marks) A E R A S I H T N I E T I R W T O N O D A E R A S I H T N I E T I R W T O N O D A E R A S I H T N I E T I R W T O N O D *P48382A0524* Turn over<br />

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