Lecture 71/31/07
Solubility vs. Solubility constant (K sp ) What is the difference? BaSO 4 (s) ⇄ Ba 2+ (aq) + SO 4 2- (aq) Ba 2+ (aq) + SO 4 2- (aq) ⇄ BaSO 4 (s)
What is the K sp for AgI if the solubility equals 9.2 x M at 25˚ C?
The K sp of AgBr at 100 ˚C is 5 x Calculate the solubility of AgBr at that temperature in molarity.
A saturated solution of silver oxalate (Ag 2 C 2 O 4 ) contains 6.9 x M of C 2 O 4 2- at 25˚C. Calculate the K sp of silver oxalate at that temperature.
The K sp of MgF 2 = 5.2 x Calculate the solubility in molarity and grams per liter.
Comparison of solubility based on K sp AgI (K sp = 8.5 x ) < AgBr (K sp = 5.4 x ) < AgCl (K sp = 1.8 x ) PbI 2 (K sp = 9.8 x ) < PbBr 2 (K sp = 6.6 x ) < PbCl 2 (K sp = 1.7 x ) Can only compare salts with same ion ratio AgCl (K sp = 1.8 x ) vs. Ag 2 CO 3 (K sp = 8.5 x ) Solubility of AgCl = 1.3 x mol/L Solubility of Ag 2 CO 3 = 1.3 x mol/L
Q vs. K sp AgBr (s) ⇄ Ag + (aq) + Br - (aq) Q = K sp Q < K sp Q > K sp