(a) A Bronsted-Lowry acid-base reaction proceeds in the net direction in which a stronger acid and stronger base form a weaker acid and weaker base. Explain. (b) The molecular scene at right depicts an aqueous solution of two conjugate acid-base pairs: HA/A − and HB/B−. The base in the first pair is represented by red spheres, and the base in the second pair by green spheres; solvent molecules are omitted for clarity. Which is the stronger acid? The stronger base? Explain.