Page 118 - Pharmaceutical_Analytical_Chemistry_1_Theoretical_Notes_Level_1

Mansoura National University
Pharm D-Clinical Pharmacy Program Level 1 Pharm. Anal. Chem. 1 (PC 101)

Quiz

1. You are provided with a solution of 0.5 M AgNO3 and 0.1 M NaCl, If you mix
10 mL of both solutions in 1L, will a precipitate of AgCl be formed or not?
-10
(Ksp AgCl = 1.7× 10 )

Answer:

• First, calculate the final concentration of each ion:
• [Ag ] = 10 × 0.5/1000 = 5× 10 M
-3
+
-3
-
• [Cl ] = 10 × 0.1/1000 = 1× 10 M
-3
-6
-3
• Q = [5× 10 ][1× 10 ] = 5× 10
• Q>Ksp
• So, a precipitate of AgCl will be formed
2. You are provided with a solution of 0.01 M AgNO3 and 0.01 M Na2CrO4, If you
mix 10 mL of both solutions in 1L, will a precipitate of Ag2CrO4 be formed or
not?
-12
• Ksp Ag2CrO4 = 1.9× 10
Answer:

• First, calculate the final concentration of each ion:

-4
+
• [Ag ] = 10 × 0.01/1000 = 1× 10 M
-
-4
• [CrO4 ] = 10 × 0.01/1000 = 1× 10 M
-12
-4 2
-4
+ 2
• Q = [Ag ] [CrO4 ] =[1× 10 ] [1× 10 ] = 1× 10
-
• Q<Ksp
• So, NO precipitate of Ag2CrO4 will be formed

113