Answer to Question #223231 in General Chemistry for Mei

Question

Solution A contains H2S 0.10 M, solution B contains Fe(NO3)2 0.10 M. a) Calculate pH value of solution A and the equilibrium concentration of H2S; HS− and S2− in solution A. b) Mix 1.00 mL solution A and 1.00 mL solution B. In the resulting solution, the precipitate will form or not? Explain by calculation. c) Calculate the solubility of FeS in solution with pH = 3.0. Given by: H2S: pKa1 = 7.02; pKa2 = 12.90; pKS(FeS) = 17,2; *b(FeOH+ ) = 10−5.92

Answer 1

[H3O+] = 1.7 × 10^−7 M. Kw is 2.9 × 10−14 at 40 °C.

= -log1.7×10^-7

=7.9