Consider the reaction: Cu(NH3)4 2+(aq) Cu2+(aq) + 4 NH3(aq) a) The reaction abov
ID: 997862 • Letter: C
Question
Consider the reaction: Cu(NH3)4 2+(aq) Cu2+(aq) + 4 NH3(aq) a) The reaction above is at equilibrium at 25C. The solution is diluted by adding deionized water at 25C. Will the reaction shift right, shift left, or remain constant? Explain your reasoning. Will Keq for the reaction INCREASE, DECREASE, or remain CONSTANT upon dilution? Explain. (If Keq decreases, does the reaction shift to the left? As k<<1 means a reactant favored reaction?) Consider the reaction: Cu(NH3)4 2+(aq) Cu2+(aq) + 4 NH3(aq) a) The reaction above is at equilibrium at 25C. The solution is diluted by adding deionized water at 25C. Will the reaction shift right, shift left, or remain constant? Explain your reasoning. Will Keq for the reaction INCREASE, DECREASE, or remain CONSTANT upon dilution? Explain. (If Keq decreases, does the reaction shift to the left? As k<<1 means a reactant favored reaction?)Explanation / Answer
a) In the given reaction, water is neither the reactant nor product. Its is only solvent. Addition of water will not shift the equilibrium according to Le Chatlier principle.
Note: If you imagine that the dilution causes more dissociation. Then, reaction shifts towards forward direction. However, concentration of each species will decrease and Keq will remains same as it is a ratio of concentration of product species to the concentration of reactant species.
b) Equilibrium constant is constant as long as temperature constant. Here temperature is 250 C. Thus Keq is constant.
(Note: By addition of reactant at constant temperature equilibrium shift towards forward direction to keep Keq value constant. similarly, by addition of product at constant temperature equilibrium shift towards backward direction to keep Keq value constant.)