Question

Le Chatelier's Principle 3. For Part Ill, use Le Châteller's Principle to explain the colour changes observed in test tubes 2 and 3 upon the addition of HC and A . Also, explain the observed colour changes in the test tubes placed in hot and cold water. (4 marks) Test Tube 2: Test Tube 3: Hot Water bath: Cold Water bath: Extension: 1. NaCl(aq) + HCl(aq) = NaCl(aq) + H2O + Cl2(g) When the above system is cooled, gas bubbles are produced. Is this reaction endothermic or exothermic? Explain. (2 marks)

Answer 1

Blue react Part III :- calor 2+ + ncé + energy F [cocent + 6H20 Pink 3. upon addition of Hellag) the equilibrium will shift in the the direction which consumption forward facilitates of ct added externally. more and more blue coloured [co cly] 2 will form. upon addition of Ag+ (aq), it will form Ag Cd (s). so cê concentration decreases. To encounter this, equilibrium will shift in the back - ward direction to form more and more pink co[H2072+. In hot-water bath, heat energy is provided externalle which causes the formation of more and more scocer as (blue) where energy is consumed in this process. In cold-water bath, removal of energy takes place. so, to maintain the equilibrium, blue [colla] transform more and more into pink {colt2027 27. Naceo (aq) + HCl(aq) ² Nack(aq) + H₂O (1) + cele cla is the only gaseous when the sižete species. This reaction is exothermic in nature as ceeline is the removal of energy, but to encounter this change , the reaction should proceed in such a direction where heat energy is evolved (characterics of an exothermic ran) the system is cooled, gas bubbles are produced