Chemistry · EQUILIBRIUM

In an acid-base equilibrium \( \text{HA(aq)} + \text{H}_2\text{O(l)} \rightleftharpoons \text{H}_3\text{O}^+\text{(aq)} + \text{A}^-\text{(aq)} \), if \( \text{HA} \) is a stronger acid than \( \text{H}_3\text{O}^+ \), in which direction will the equilibrium primarily lie and why?

1. Backward direction, because weaker acid donates a proton to weaker base
2. Backward direction, because strong bases always remain in unreacted form
3. Equilibrium does not shift as both sides have identical acid strengths
4. Forward direction, because stronger acid donates a proton to stronger base forming weaker species