chemistry 2

10.       Among the solubility rules previously discussed is the statement: Carbonates, phosphates, borates, and arsenates—except those of the ammonium ion and the alkali metals—are insoluble. (a) Write the expression for the equilibrium constant for the reaction represented by the equation CaCO3(s) ⇌ Ca2+(aq) + CO3 −(aq). Is Kc > 1, < 1, or ≈ 1? Explain your answer. (b) Write the expression for the equilibrium constant for the reaction represented by the equation 3Ba2+(aq) + 2PO4 3−(aq) ⇌ Ba3 (PO4)2(s). Is Kc > 1, < 1, or ≈ 1? Explain your answer.

16.       Write the mathematical expression for the reaction quotient, Qc, for each of the following reactions:

(a) N2(g) + 3H2(g) ⇌ 2NH3(g)

b) 4NH3(g) + 5O2(g) ⇌ 4NO(g) + 6H2 O(g)