You need to re-read your text about Le Chatelier's Principle. That principle says, in simple terms, that a system in equilibrium will try to undo what we do to it.
Zn^2+(aq) + 2OH^-(aq) ==> Zn(OH)2(s)
a. If HCl is added, it reacts with the OH (H^+ + OH^- ==> H2O) which reduces the OH^-. So the system will shift to increased the OH. The ONLY way it can do that (three choices are: shift right, shift left, doesn't shift) is to shift to the left.
b. If you add a small amount of OH^- you increase OH so the system will try to reduce that and the only way it can do it is to make the reaction go forward (shift to the right).
c. They tricked you on this one. A LARGE amount of NaOH makes this reaction.
Zn(OH)2(s) + 2OH^-(aq) ==> Zn(OH)4^2-(aq)
So addition of a large amount of NaOH dissolves Zn(OH)2^2- so the reaction goes to the right.
Zn^2+(aq) + 2OH^-(aq) ----> Zn(OH)2(s)
a) how the addition of HCl affects the equilibrium? my answer is it will shift to the right
b) how the addition of a small amount of NaOh affects the equilibrium?my answer is it will shift to the left
c) how the addition of a large amount of NaOH affects the equilibrium? my answer is it will shift to the left
d) rewrite the net equation for this equilibrium and indicate if this is an exothermic or endothermic reaction? my ansewr is endothermic reaction
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thanks for the explanation pls is it endothermic or exothermic reaction i'm confused with this
2 answers