Which elements are more likely to form acidic oxides? Basic oxides? Amphoteric oxides?

Calculations with Ka & Kb Values • for a conjugate acid-base pair, Ka x Kb = Kw, where Kw = 1.0 x 10^-14 at 25˚C ex. Is a solution of NH4HC2O4 at 25˚C acidic, basic, or neutral • Ka C2H2O4 = 5.6 x 10^-2 Kb NH3 = 1.8 x 10^-5 Solve for new Ka for NH4+ + H2O⁶NH3 + H3O+ Ka* = 1.0 x 10^-14 = 5.56 x 10^-10 *Use Ka* = Kw 1.8 x 10^-5 Kb Solve for new Kb for C2H2O4 + H2O⁶HC2H2O4+ + OH- Kb* = 1.0 x 10^-14 = 1.79 x 10^-13 *Use Kb* = Kw 5.6 x 10^-2 Ka Choose bigger K value 5.56 x 10^-10 > 1.79 x 10^-13 Since Ka* > Kb*, NH4HC2O4 is acidic (at 25˚C). • ex. Calculate pH of a 0.10 M NH4NO3 solution. Kb NH