An aqueous solution contains 0.10 M H₂S and 0.20 M HCl. If the equilibrium constants for the formation of HS^– from H₂S is 1.0 $$\times$$ 10^–7 and that of S^2- from HS^– ions is 1.2 $$\times$$ 10^–13 then the concentration of S^2- ions in aqueous solution is :

An aqueous solution contains an unknown concentration of Ba²⁺. When 50 mL of a 1 M solution of Na₂SO₄ is added, BaSO₄ just begins to precipitate. The final volume is 500 mL. The solubility product of BaSO₄ is 1 $$\times$$ 10^–10. What is the original concentration of Ba²⁺?

For 1 molal aqueous solution of the following compounds, which one will show the highest freezing point?

Which of the following lines correctly show the temperature dependence of equilibrium constant K, for an exothermic reaction?