Question

Question 1:
We place 0.895 mol of a weak acid, HA, and 13.0 g of NaOH in enough water to produce 1.00 L of solution. The final pH of this solution is 4.01 . Calculate the ionization constant, K_b, of A^-(aq).

Question 2:
HA is a weak acid with a pK_a value of 3.76 . What is the pH of a buffer solution that is 0.359 M in HA and 0.844 M in NaA? What is its pH after the addition of 14.6 g of HCl to 2.000 L of this buffer solution? Assume the volume remains fixed at 2.000 L.

Question 3:
The solubility product, K_sp, of Al(OH)₃(s) is 1.0 x 10^-33. What is its solubility (in g/L) in an aqueous solution of NaOH with a pH of 12.76 ?

Question 4:
The formation constant, K_f, of PbCl₄^2-(aq), Pb²⁺(aq) + 4 Cl^-(aq) ⇌ PbCl₄^2-(aq), is 2.5 x 10¹⁵. What are the equilibrium concentrations of Pb²⁺(aq), Cl^-(aq), and PbCl₄^2-(aq) if we add 0.122 mol of Pb(NO₃)₂ to 1.000 L of a 0.842 M aqueous solution of NaCl? Assume the volume remains fixed at 1.000 L.

Answer 1

Please go through the solution,