Question

In: Chemistry

Consider the effect of ionic strength, find the concentrations of Ag+, CN-, and HCN in a...

Consider the effect of ionic strength, find the concentrations of Ag⁺, CN^-, and HCN in a saturated solution of AgCN whose pH is fixed at 9.00 (consider the effect of ionic strength and activities. use a method of successive approximations, until your answers from two iterations agree to within 5%).

Equilibria:

AgCN (s) <---> Ag⁺ + CN^- Ksp= 2.2 x 10^-16

CN^- + H₂O <---> HCN + OH^- Kb= 1.6 x 10^-5

Expert Solution

AgCN_(s)[Ag+_(aq)][CN-_(aq)]

The silver and cyanide ion concentration formed is considered as 'x'.applying solubility product,

Ksp=x²

2.2*10^-16 =x²

^{X=√2.2*10^-16}

^{=1.48*10^-8 moldm-3}

^{[Ag+]=[CN-]=1.48*10^-8moldm-3}

^{Since pH =9,solution is basic so K_b be
applied.}

Kb=[HCN][OH-]/[CN-]

Concentration of water is a constant=1

From ph ,[OH-] can be found.

[H+][OH-]=10^14

[OH-]=1*10^5 moldm-3

(1.6*10^-5×1.48*10^-8)/1*10^-5=[HCN]

[HCN]=2.368*10^-8 moldm-3

queen_honey_blossom answered 2 years ago

Use systematic equilibria calculation to find the concentrations of Ag+, CN-, and HCN in a saturated solution of AgCN whose pH is fixed at 9.00

Use systematic equilibria calculation to find the concentrations of Ag+, CN-, and HCN in a saturated solution of AgCN whose pH is fixed at 9.00. Consider the following equilibria. AgCN(s)  Ag+ + CN- Ksp = 2.2 x 10-16 CN- + H2O  HCN (aq) + OH- Kb = 1.6 x 10-5

Consider the following dissociation of the weak acid, HCN: HCN(aq) ⇌ CN−(aq) + H+(aq) K =...

Consider the following dissociation of the weak acid, HCN: HCN(aq) ⇌ CN−(aq) + H+(aq) K = 6.2×10-10 A solution is made with an initial concentration of 2.60 M HCN. At equilibrium, what is the concentration of H+ ions in solution? (Hint: You may use the 5% approximation.) ?M

a. What is the pH of a 0.040 M solution of HCN? Find the concentrations of...

a. What is the pH of a 0.040 M solution of HCN? Find the concentrations of all the major species in the solution? [HCN], [H3O+], [CN-]

Determine [Zn2 ], [CN–], and [HCN] in a saturated solution of Zn(CN)2 in a buffer with...

Determine [Zn2 ], [CN–], and [HCN] in a saturated solution of Zn(CN)2 in a buffer with a pH of 1.060. The Ksp for Zn(CN)2 is 3.0 × 10–16. The Ka for HCN is 6.2 × 10–10. Because a buffer is present, you cannot know the charge balance equation.

Consider the dissociation of aqueous HCN at 25°C: HCN(aq) --> H+(aq) + CN–(aq) K = 6.2×10–10...

Consider the dissociation of aqueous HCN at 25°C: HCN(aq) --> H+(aq) + CN–(aq) K = 6.2×10–10 . a) Compute ΔG° at 25°C. b) If 0.120 mol of HCN is dissolved to make 200. mL of solution, then what are the equilibrium concentrations of all of the species? c) Suppose 0.040 mol of HCN is dissolved in the same solution without appreciably increasing the volume. Compute the derivative dG/dξ for the system before it has a chance to re-establish equilibrium. Use...

Determine [Zn2 ], [CN–], and [HCN] in a saturated solution of Zn(CN)2 with a fixed pH...

Determine [Zn2 ], [CN–], and [HCN] in a saturated solution of Zn(CN)2 with a fixed pH of 2.550. The Ksp for Zn(CN)2 is 3.0 × 10–16. The Ka for HCN is 6.2 × 10–10. 1) Zn(CN)2 (s) --> Zn 2+ (aq) + 2 CN- (aq) 2) CN- (aq) + H2O (l) --> HCN (aq) + OH- (aq) 3) H2O (l) --> H+ (aq) + OH- (aq)

Determine [Zn2+], [CN−], and [HCN] in a saturated solution of Zn(CN)2 with a fixed pH of...

Determine [Zn2+], [CN−], and [HCN] in a saturated solution of Zn(CN)2 with a fixed pH of 3.530. The ?sp for Zn(CN)2 is 3.0×10−16. The ?a for HCN is 6.2×10−10. [Zn2+]= [HCN]= [CN−]

balance the following redox reaction in basic solution Ag(s)+CN-(aq)+ O2(g) -->Ag (CN)2- (aq) cyanide is not...

balance the following redox reaction in basic solution Ag(s)+CN-(aq)+ O2(g) -->Ag (CN)2- (aq) cyanide is not participating in the electrochemical reaction but does associate with the silver ion formed in a second association reaction. Balance the electrochemistry first and then add in the cyanide in by adding an associative reaction to the redox reaction.

Determine [Zn2 ], [CN–], and [HCN] in a saturated solution of Zn(CN)2 with a fixed pH of 2.780.

Determine [Zn2 ], [CN–], and [HCN] in a saturated solution of Zn(CN)2 with a fixed pH of 2.780. The Ksp for Zn(CN)2 is 3.0 × 10–16. The Ka for HCN is 6.2 × 10–10.The hint says: Use the systematic treatment of equilibrium to solve this problem. 1. Write the pertinent reactions. 2. Write the charge balance equation. 3. Write the mass balance equations. 4. Write the equilibrium constant expressions for each reaction. 5. Count the equations and unknowns. 6. Solve...

Silver plating processes use Ag(CN)2- as the source of Ag+ in solution. To make the solution:...

Silver plating processes use Ag(CN)2- as the source of Ag+ in solution. To make the solution: 4.0 L of 3.00 M NaCN and 50.0 L of 0.200 M AgNO3 are combined. (a) What is the concentration of free Ag+ ions in solution? (b) Why is AgCl not used in this process? NOTE: We have not yet introduced the equilibrium constant Kf. An answer is needed that gets around Kf or slowly introduces the concept. Thanks! (Jespersen 7th edition 21.98)