   Chapter 19, Problem 18PS

Chapter
Section
Textbook Problem

Calculate the value of E° for each of the following reactions. Decide whether each is product-favored at equilibrium in the direction written. [Reaction (d) is carried out in basic solution.] (a) Br2(ℓ) + Mg(s) → Mg2+(aq) + 2 Br−(aq) (b) Zn2+(aq) + Mg(s) → Zn(s) + Mg2+(aq) (c) Sn2+(aq) + 2 Ag+(aq) → Sn4+(aq) + 2Ag(s) (d) 2 Zn(s) + O2(g) + 2 H2O(ℓ) + 4 OH−(aq) → 2[Zn(OH)4]2−(aq)

a)

Interpretation Introduction

Interpretation:

The Eo value of the given reaction has to be determined and has to decide whether it is a product favoured at equilibrium in the direction.

a) Br2(l) +Mg(s)  Mg2+(aq) + 2Br-(aq)

Concept introduction:

Electrochemical cells:

In this type of cells, chemical energy is converted into electrical energy.

In all electrochemical cells, oxidation occurs at anode and reduction occurs at cathode.

An anode is indicated by negative sign and cathode is indicated by the positive sign.

Electrons flow in the external circuit from the anode to the cathode.

In the electrochemical cells two half cells are connected with salt bridge. It allows the cations and anions to move between the two half cells.

Under certain conditions a cell potential is measured it is called as standard potential (Ecello).

Standard potential (Ecello) can be calculated by the following formula.

Ecello=Ecathodeo-Eanodeo

The Ecello value is positive, the reaction is predicted to be product favoured at equilibrium.

The Ecello value is negative, the reaction is predicted to be reactant favoured at equilibrium.

Explanation

The given reaction is as follows.

Br2(l) +Mg(s)  Mg2+(aq) + 2Br-(aq)

Let’s write the half reactions:

At anode:Oxidation:  Mg (s) Mg2+(aq) +2e-At cathode:Reduction: Br2(l)+2e-

b)

Interpretation Introduction

Interpretation:

The Eo value of the given reaction has to be determined and has to decide whether it is a product favoured at equilibrium in the direction.

b) Zn2+(aq) + Mg(s) Zn(s) + Mg2+(aq)

Concept introduction:

Electrochemical cells:

In this type of cells, chemical energy is converted into electrical energy.

In all electrochemical cells, oxidation occurs at anode and reduction occurs at cathode.

An anode is indicated by negative sign and cathode is indicated by the positive sign.

Electrons flow in the external circuit from the anode to the cathode.

In the electrochemical cells two half cells are connected with salt bridge. It allows the cations and anions to move between the two half cells.

Under certain conditions a cell potential is measured it is called as standard potential (Ecello).

Standard potential (Ecello) can be calculated by the following formula.

Ecello=Ecathodeo-Eanodeo

The Ecello value is positive, the reaction is predicted to be product favoured at equilibrium.

The Ecello value is negative, the reaction is predicted to be reactant favoured at equilibrium.

c)

Interpretation Introduction

Interpretation:

The Eo value of the given reaction has to be determined and has to decide whether it is a product favoured at equilibrium in the direction.

c) Sn2+(aq) + 2Ag+(aq) Sn4+(aq) + 2Ag(s)

Concept introduction:

Electrochemical cells:

In this type of cells, chemical energy is converted into electrical energy.

In all electrochemical cells, oxidation occurs at anode and reduction occurs at cathode.

An anode is indicated by negative sign and cathode is indicated by the positive sign.

Electrons flow in the external circuit from the anode to the cathode.

In the electrochemical cells two half cells are connected with salt bridge. It allows the cations and anions to move between the two half cells.

Under certain conditions a cell potential is measured it is called as standard potential (Ecello).

Standard potential (Ecello) can be calculated by the following formula.

Ecello=Ecathodeo-Eanodeo

The Ecello value is positive, the reaction is predicted to be product favoured at equilibrium.

The Ecello value is negative, the reaction is predicted to be reactant favoured at equilibrium.

d)

Interpretation Introduction

Interpretation:

The Eo value of the given reaction has to be determined and has to decide whether it is a product favoured at equilibrium in the direction.

d) 2Zn(s) + O2(g) + 2H2O(l) + 4OH-(aq) 2[Zn(OH)4]2-(aq)

Concept introduction:

Electrochemical cells:

In this type of cells, chemical energy is converted into electrical energy.

In all electrochemical cells, oxidation occurs at anode and reduction occurs at cathode.

An anode is indicated by negative sign and cathode is indicated by the positive sign.

Electrons flow in the external circuit from the anode to the cathode.

In the electrochemical cells two half cells are connected with salt bridge. It allows the cations and anions to move between the two half cells.

Under certain conditions a cell potential is measured it is called as standard potential (Ecello).

Standard potential (Ecello) can be calculated by the following formula.

Ecello=Ecathodeo-Eanodeo

The Ecello value is positive, the reaction is predicted to be product favoured at equilibrium.

The Ecello value is negative, the reaction is predicted to be reactant favoured at equilibrium.

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 