A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of NH⁺₄ is 0.20 M. If the equilibrium constant, K_b for NH₃ equals 1.8 $$ \times $$ 10^$$-$$5, what is the pH of this solution? (log 2.7 = 0.43)

Which of the following is least likely to behave as Lewis base?

If pH of a saturated solution of Ba(OH)₂ is 12, the value of its K_sp is

In a buffer solution containing equal concentration of B^$$-$$ and HB, the K_b for B^$$-$$ is 10^$$-$$10. The pH of buffer solution is