   # Will a precipitate of Mg(OH) 2 form when 25.0 mL of 0.010 M NaOH is combined with 75.0 mL of a 0.10 M solution of magnesium chloride? ### Chemistry & Chemical Reactivity

9th Edition
John C. Kotz + 3 others
Publisher: Cengage Learning
ISBN: 9781133949640

#### Solutions

Chapter
Section ### Chemistry & Chemical Reactivity

9th Edition
John C. Kotz + 3 others
Publisher: Cengage Learning
ISBN: 9781133949640
Chapter 17, Problem 70PS
Textbook Problem
12 views

## Will a precipitate of Mg(OH)2 form when 25.0 mL of 0.010 M NaOH is combined with 75.0 mL of a 0.10 M solution of magnesium chloride?

Interpretation Introduction

Interpretation:

Whether precipitation of Mg(OH)2 occurs or not on addition of 25 ml 0.01 MNaOH to 75ml 0.1 M MgCl solution has to be predicted.

Concept introduction:

Solubility product constant,Ksp is equilibrium constant and is defined as the product of the equilibrium concentration of the ions of the salt raised to the power of their coefficients in the balanced chemical equation.

The expression for Ksp of a salt is given as,

AxBy(s)xAy+(aq)+yBx(aq)Ksp=[Ay+]x[Bx]y

Here,

• [Ay+] and [Bx] are equilibrium concentration.

Reaction quotient, Q, for a reaction is defined as the product of the concentration of the ions at any time of the reaction (other than equilibrium time ) of the salt raised to the power of their coefficients in the balanced chemical equation.

The expression for Q of a salt is given as,

AxBy(s)xAy+(aq)+yBx(aq)Ksp=[Ay+]x[Bx]y

Here,

• [Ay+] and [Bx] are the concentration at any time except equilibrium.
1. 1. If Q=Ksp, this implies that the solution is saturated solution and the concentration of the ions have reached their maximum limit.
2. 2. If Q<Ksp, this implies that the solution is not saturated and more salt can be added to the solution or the salt present in the solution already will dissolve more until the precipitation starts.
3. 3. If Q>Ksp, this implies that the solution is oversaturated and precipitation of salt will occur.

### Explanation of Solution

Value of reaction quotient,Q, is calculated and compared with the value of Ksp for Mg(OH)2.

Given:

Refer to the Appendix J in the textbook for the value of Ksp

The value of solubility product constant,Ksp, for Mg(OH)2 is 5.6×1012.

Mg(OH)2 is dissociated as follows in water,

Mg(OH)2(s)Mg2+(aq)+2OH(aq)

The expression of Q for Mg(OH)2 is,

Q=[Mg2+][OH1]2 (1)

millimoles of Mg2+=75×0.1=7.5millimoles of OH=25×0.01=0.25

Total volume of the solution is 100 ml.

Concentration of Magnesium ions in the solution is,

[Mg2+]=7.5100=7.5×102 M

Concentration of hydroxide ions in the solution is,

[OH1]=0

### 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

Find more solutions based on key concepts
Which of these advantages do sports drinks provide over plain water? They taste good and so may lead people to ...

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

One yard is slightly ___ than 1 meter. (1.4)

An Introduction to Physical Science

What are sister chromatids?

Human Heredity: Principles and Issues (MindTap Course List)

A uniformly charged insulating rod of length 14.0 cm is bent into the shape of a semicircle as shown in Figure ...

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