   Chapter 20, Problem 16PS

Chapter
Section
Textbook Problem

Silver ions have long been known to have biocidal properties. The increasing use of silver for this purpose has led to greater silver concentrations in waste water, and there has been some concern about it. However, recent studies found that the silver was largely put back into the environment as Ag2S. The solubility of this sulfide is 1.4 × 10−4 g/L. (a) Estimate the for K′sp for Ag2S. (See Table 18b in Appendix J.) (b) How does the solubility of Ag2S change as the pH decreases?

(a)

Interpretation Introduction

Interpretation:

The Ksp value for the given sulfide should be estimated.

Concept introduction:

• KSP for a general reaction, AB(s)A(aq)++B(aq)- is,

KSP=[A+][B-]

• Molarity is one of the concentrations expressing terms and it is equal to the moles of solute divided by the liter of solution.

Molarity(M)=MolesofsoluteLitersofsolution

• Numberofmoles=MassingramsMolarmassofthesubstance
• pH=-log[H3O+] it is used to know about the nature of the substance, whether it  is acidic, basic or neutral.
Explanation

Given,

The dissociation of Ag2S in aqueous solution can be written as,

Ag2S(s)2Ag(aq)++S(aq)

The solubility of silver sulfide Ag2S is 1.4×10-4g/L

This means 1.4×10-4g of Ag2S is dissolved in 1L of the solution.

Number of moles of Ag2S can be calculated as follows,

NumberofmolesofAg2S=1.4×104g247.8g/mol=5

(b)

Interpretation Introduction

Interpretation:

The change in the solubility of Ag2S when pH decreases should be determined.

Concept introduction:

• The Le Chateliers principle states that the position of equilibrium will move in such a way as to counteract the change in concentration, pressure, and temperature.

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

What is motion?

An Introduction to Physical Science

What is meant by biological evolution?

Human Biology (MindTap Course List)

What causes an aging giant star to produce a planetary nebula?

Horizons: Exploring the Universe (MindTap Course List)

What is physically exchanged during crossing over?

Human Heredity: Principles and Issues (MindTap Course List) 