BuyFindarrow_forward

Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074

Solutions

Chapter
Section
BuyFindarrow_forward

Chemistry & Chemical Reactivity

10th Edition
John C. Kotz + 3 others
ISBN: 9781337399074
Textbook Problem

Solid silver iodide, AgI, can be dissolved by adding aqueous sodium cyanide. Calculate Knet the following reaction.

A g I ( s ) + 2   C N   [ A g ( C N ) 2 ] ( a q ) + I ( a q )

Interpretation Introduction

Interpretation:

The value of net equilibrium constant Knet has to be calculated for the given reaction.

Concept introduction:

Some metal ions when present in an aqueous solution containing anions or neutral species called Lewis base or ligands having a tendency to donate electron pairs to metal ions then complex ion formation will take place.

Example of metal ions that form complex ions includes,Cd2+,Fe2+,Zn2+,Ni2+ etc.

Example of Lewis bases includes,NH3,OH etc.

The complex ion remains in equilibrium with the metal ion and the ligand called complex ion formation equilibrium and the equilibrium constant is called as formation constant Kf.

A larger value of Kf implies that the complex ion formed is more stable. Kf is the measure of the strength of the interaction between the metal ions and the Lewis base to form the complex ion.

For example for general complex ion formation reaction,

  xM+yL[MxLy]

Kf can be given as

  Kf=[MxLy][M]x[L]y

 Here,

  • [MxLy] is the equilibrium concentration of complex ion.
  • [M] is the equilibrium concentration of metal ion.
  • [L] is the equilibrium concentration of the ligand.
  • x and y are the coefficients of metal ion and ligand respectively.

Complex ions are stable and thus formation of these increase the solubility of the salt containing the metal ions same as in complex ions. Effect of complex ion formation on solubility of salt can be explained as below,

AgBr when dissolved in water does not dissolve completely and dissociates as follows,

  AgBr(s)KspAg+(aq)+Br(aq) (1)

For this reaction Ksp expression is,

Ksp=[Ag+][Br]

Ag+ ions are capable of forming complex with ligand so when aqueous ammonia solution (strong ligand) is added to the saturated solution of AgBr, Ag+ ions present in the solution form complex with NH3.

  Ag+(aq)+2NH3(aq)Kf[Ag(NH3)2]+(aq) (2)

The expression for formation constant Kf is given as,

Kf=[[Ag(NH3)2]+][Ag+][NH3]2

Complex formation leads to the decrease in the concentration of the Ag+ ions in the solution, as a result, according to Le Chatelier’s principle the equilibrium in equation (1) move in the forward direction producing more of the Ag+ ions and the solubility of the slightly soluble salt AgBr increases.

Adding two equilibrium equation (1) and (2) new overall equilibrium constant can be defined.

Net chemical equation:

  Ag+(aq)+2NH3(aq)Knet[Ag(NH3)2]+(aq)+Br(aq) (3)

Net equilibrium constant can be given as,

Knet=(Ksp)(Kf) (4)

Explanation

The value of net equilibrium constant, Knet for the given reaction is calculated below.

Given:

Refer to the Appendix J and K in the textbook for the value of Ksp and Kf respectively.

The value of solubility product constant, Ksp for AgI is 8.5×1017 .

The value of formation constant, Kf for [Ag(CN)2] is 1.3×1021.

AgI dissociates as follows in water,

  AgI(s)KspAg+(aq)+I(aq) (5)

Ag+ ions present in solution undergo complex formation with cyanide ions to form [Ag(CN)2] complex. The reaction for complex formation is given as,

  Ag+(aq)+2CN1(aq)Kf[Ag(CN)2](aq) (6)

Add equation (5) and (6) to find the net chemical equation

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Chapter 17 Solutions

Show all chapter solutions add
Sect-17.4 P-17.11CYUSect-17.5 P-17.12CYUSect-17.5 P-17.13CYUSect-17.5 P-17.14CYUSect-17.6 P-17.15CYUSect-17.6 P-17.16CYUSect-17.6 P-1.1ACPSect-17.6 P-1.2ACPSect-17.6 P-1.3ACPSect-17.6 P-1.4ACPSect-17.6 P-1.5ACPSect-17.6 P-2.1ACPSect-17.6 P-2.2ACPCh-17 P-1PSCh-17 P-2PSCh-17 P-3PSCh-17 P-4PSCh-17 P-5PSCh-17 P-6PSCh-17 P-7PSCh-17 P-8PSCh-17 P-9PSCh-17 P-10PSCh-17 P-11PSCh-17 P-12PSCh-17 P-13PSCh-17 P-14PSCh-17 P-15PSCh-17 P-16PSCh-17 P-17PSCh-17 P-18PSCh-17 P-19PSCh-17 P-20PSCh-17 P-21PSCh-17 P-22PSCh-17 P-23PSCh-17 P-24PSCh-17 P-25PSCh-17 P-26PSCh-17 P-27PSCh-17 P-28PSCh-17 P-29PSCh-17 P-30PSCh-17 P-31PSCh-17 P-32PSCh-17 P-33PSCh-17 P-35PSCh-17 P-36PSCh-17 P-37PSCh-17 P-38PSCh-17 P-39PSCh-17 P-40PSCh-17 P-41PSCh-17 P-42PSCh-17 P-43PSCh-17 P-44PSCh-17 P-45PSCh-17 P-46PSCh-17 P-47PSCh-17 P-48PSCh-17 P-49PSCh-17 P-50PSCh-17 P-51PSCh-17 P-52PSCh-17 P-53PSCh-17 P-54PSCh-17 P-55PSCh-17 P-56PSCh-17 P-57PSCh-17 P-58PSCh-17 P-59PSCh-17 P-60PSCh-17 P-61PSCh-17 P-62PSCh-17 P-63PSCh-17 P-64PSCh-17 P-65PSCh-17 P-66PSCh-17 P-67PSCh-17 P-68PSCh-17 P-69PSCh-17 P-70PSCh-17 P-71PSCh-17 P-72PSCh-17 P-73PSCh-17 P-74PSCh-17 P-75PSCh-17 P-76PSCh-17 P-77GQCh-17 P-78GQCh-17 P-79GQCh-17 P-80GQCh-17 P-81GQCh-17 P-82GQCh-17 P-83GQCh-17 P-84GQCh-17 P-85GQCh-17 P-86GQCh-17 P-87GQCh-17 P-88GQCh-17 P-89GQCh-17 P-90GQCh-17 P-91GQCh-17 P-92GQCh-17 P-93GQCh-17 P-94GQCh-17 P-95GQCh-17 P-96GQCh-17 P-97GQCh-17 P-98GQCh-17 P-99GQCh-17 P-100GQCh-17 P-101ILCh-17 P-102ILCh-17 P-103ILCh-17 P-104ILCh-17 P-105ILCh-17 P-106ILCh-17 P-107ILCh-17 P-108ILCh-17 P-109ILCh-17 P-110ILCh-17 P-111ILCh-17 P-112ILCh-17 P-113SCQCh-17 P-114SCQCh-17 P-115SCQCh-17 P-116SCQCh-17 P-117SCQCh-17 P-118SCQCh-17 P-119SCQCh-17 P-120SCQ

Additional Science Solutions

Find more solutions based on key concepts

Show solutions add

Studies of populations in which observation is accompanied by experimental manipulation of some population memb...

Nutrition: Concepts and Controversies - Standalone book (MindTap Course List)

Speed is a(n) ___ quantity. (2.2)

An Introduction to Physical Science

How many autosomes are present in a body cell of a human being? In a gamete?

Human Heredity: Principles and Issues (MindTap Course List)

The charge per unit length on a long, straight filament is 90.0 C/m. Find the electric field (a) 10.0 cm, (b) 2...

Physics for Scientists and Engineers, Technology Update (No access codes included)

When was the first set of laws governing the allocation of ocean resources proposed?

Oceanography: An Invitation To Marine Science, Loose-leaf Versin