[Big-Daddy]

What is meant by "position of equilibrium" and what are the steps taken to calculate it (for a given set of initial concentrations at a set temperature and pressure)?

[Hunter2]

This means is the equilibrium on the side of the educt or products and how far it is. It will be expressed by the K.

A+B => C+D   K = c(C)*c(D)/(c(A)*c(B))

[Big-Daddy]

This means is the equilibrium on the side of the educt or products and how far it is. It will be expressed by the K.

A+B => C+D   K = c(C)*c(D)/(c(A)*c(B))

You speak of the equilibrium constant, not the position of the equilibrium. Let me point out the difference. K_eq stays constant if I change the concentration of the reactants or products by adding or taking some. But if I add A, then the position shifts, in the sense that the "equilibrium moves to the right" (more of C and D are being produced). But how does one calculate something like this?