So if you had the equilibrium $\ce{A <--> B}$ and you increase the concentration of A. I understand that equilibrium will shift to the right. To say this (I believe) is to say that the $\ce{A -> B}$ reaction is favoured. But when at equilibrium again will the position of equilibrium be back in its original position, as I believe the position of equilibrium to be defined as the amount of A relative to B.
If this is true, does it follow that a shift in equilibrium does not necessarily mean a permanent change in the position?
If it was a $\ce{A + B <--> C}$ equilibrium and you increase the concentration of A the equilibrium will shift to the right. How would you determine if the position had changed at equilibrium?
Thanks very much.