Mg(OH)2=Mg2 + 2OH-

a) which species would react with if an acid H+ is added to the mixture? my answer is the equation will shift to the right (product)
b) would this cause a deficit or excess? my answer is excess
c) what would you predict would be observed by adding the acid? i don't know with this one pls help?
d)in c above use lechatelier's principle to explain the observation.
pls i need help this is one of the postlab questions which is not related to the experiment were having.

1 answer

I think you have not answered a correctly. The question doesn't ask in a which direction the reaction shifts; it asks which ion will react with H^+ if an acid is added. The answer is it will react with the OH^-.
b. Will this cause a deficit or excess OF WHAT? If they mean OH, it will cause a deficit since you will be using OH to react with the H^+.
c. More Mg(OH)2 solid will dissolve.
d. Le Chatlier's Principle, in simple words, says that a system in equilibrium will try to undo what we do to it. So if we add H^+, that reacts with OH decreasing the OH^-, the reaction will shift to the right to replace the OH^- we've removed, and that means more solid Mg(OH)2 will dissolve.