Using your knowledge of the molecular basis for acid strength, explain the following observations:

Question

i) HClO4 is a stronger oxyacid than H2SeO4
ii) Nitrite (NO2-) is a stronger base than sulphite (SO32-)

Answer 1

i. electronegativity Cl > Se
ii. more O atoms in the material means stronger acid. That makes [SO3]^2- a stronger acid making [NO2]^- a weaker acid (stronger base).