Water as a reactant in equilibrium...

[ice_blockie]

If say water was a reactant in an equilibrium reaction, what effect is more significant:
a) the increase of one reactant causes the equilibrium position to shift right OR
b) the concentrations of everything reduce, but according to LCP, adjustment is done by shifting to the side with more molecules...

Any ideas?

[Collin Li]

They are (sort of) mutually exclusive effects:

Effect b requires it to be an aqueous system, where water is the solvent (by definition), otherwise the addition of water would not be a dilution. Here, we ignore water from the equilibrium constant, so effect a does not cause disequilibrium (no change to the reaction quotient).

I guess effect a can still be thought to be happening in conjunction with event b, but the argument is that the concentration of the water doesn't change much (changes from ~55, pure water, to nothing drastically different from that), so effect a is less significant in this case.

[ice_blockie]

Oh, okay I understand. I was just thinking about that today and confused myself, verbal stoush with myself...not nice thanks coblin