Enter your answer in the provided box. 1. Calculate the moalr solubility of AgBr

Question

Enter your answer in the provided box.

1. Calculate the moalr solubility of AgBr in a 2.7 M NH3 solution

= ______________________M

Select all that apply

2. The molar solubility of AgCl in 6.5 x10^-3 M AgNO3 is 2.5x10^-8 M. In deriving Ksp from these data, which of the following assumptions is (are) reasonable

A. Ksp is the same as solubility

B. Ksp of AgCl is the same in 2.5x10^-8 M AgNO3 as in pure water

C. Solubility of AgCl is independent of the concentration of AgNO3

D. [Ag+] does not change significantly upon addition of AgCl to 6.5x10^-3 M AgNO3

E. [Ag+] after the addition of AgCl to 6.5x10^-3 M AgNO3 is the same as it would be in pure water

3. A 265 mL solution of NaCl was electrolyzed for 6.90 min. If the pH of the final solution was 12.02, calculate the average current used? = __________________A

4. What is the standard emf of a galvanic cell made of a Pb electrode in a 1.0 M Pb(NO3)2 solution and a Al electrode in a 1.0 M Al(NO3)3 solution at 25C?

Ecell= _____________________V

please show all work to get all stars!

Explanation / Answer

1.   AgBr = > Ag+ + Br- Ksp = [Ag+ ] [ Br-] = 7.7 * 10 ^ - 13

Ag+ + 2NH3 <=> Ag(NH3)2+

Kf = [Ag(NH3)2+] / [Ag+] [ NH3-] ^2 = 1.7 * 10 ^ 7

almost every Ag- ion formed from AgBr dissolution is transformed into the complex. ( Kf is very large and favours the RHS)

For each Ag + that dissolves 1 Br- ion is released

so the [Br-] ~ [Ag(NH3)2+] = c

Combining the equation and solving for [Ag+}

c^2 = Ksp * Kf * [NH3] ^2

c^2 = 7.7 * 10 ^-13 * 1.70 ^7 * (2.7-2c) ^2

c = 9 * 10 ^ 3 moles per liter

[Br-] which results from the dissolution of the AgBr = 9 * 10 -3 moles/ liter

solubility of AgBr in 2.7 M NH3 is approximately 9 * 10 ^ -3 molar

2.D. [Ag+] does not change significantly upon addition of AgCl to 6.5x10^-3 M AgNO3

E. [Ag+] after the addition of AgCl to 6.5x10^-3 M AgNO3 is the same as it would be in pure water

3.

Related Questions

Navigate

• Browse (All)
• Browse E
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.