Question

Equilibrium

Answer 1

Does equ. lie to the left of right? This is an example of a test question, where we aren't allowed to use calculators. So i can't calculate pka and Ka etc... I have to base it on stability.
I don't know how to do that.

Answer 2

This first thing to look at are ions, because they're typically more unstable than neutral molecules.

On the left the ion is a methoxy group, which has the negative charge localized to the oxygen atom. Oxygen is pretty electronegative, so though this is an ion, it's relatively stable.

On the right you have the negative charge localized to a primary carbon atom. Carbon is not nearly as electronegative, and it's also attached to only one other carbon atom (by a triple bond no less), meaning it can't share the electron easily with nearby atoms. This molecule if therefore more unstable.

For these reasons, the left side of the reaction will be favored, because it contains the more stable anion!