/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 62 Consider only the species (at st... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 18: Problem 62

Consider only the species (at standard conditions) $$$\mathrm{Br}^{-}, \quad \mathrm{Br}_{2}, \quad \mathrm{H}^{+}, \quad \mathrm{H}_{2}, \quad \mathrm{La}^{3+}, \quad \mathrm{Ca}, \quad \mathrm{Cd}$$ in answering the following questions. Give reasons for your answers. a. Which is the strongest oxidizing agent? b. Which is the strongest reducing agent? c. Which species can be oxidized by \(\mathrm{MnO}_{4}^{-}\) in acid? d. Which species can be reduced by \(\mathrm{Zn}(s) ?\)

Short Answer

Expert verified
a) Strongest oxidizing agent: \(\mathrm{Br}_{2}\) b) Strongest reducing agent: \(\mathrm{Ca}\) c) Species that can be oxidized by \(\mathrm{MnO}_{4}^{-}\) in acid: \(\mathrm{H_2}, \mathrm{La}, \mathrm{Ca}, \mathrm{Cd}, \mathrm{Zn}\) d) Species that can be reduced by \(\mathrm{Zn}(s) :\) \(\mathrm{Br}_2, \mathrm{H}_2, \mathrm{Cd}\)

Step by step solution

01

Understanding reduction potentials

Reduction potentials measure the tendency of a chemical species to be reduced or gain electrons. Positive reduction potentials indicate a greater tendency for a species to be reduced, while negative values signify a lower tendency for reduction. In general, species with higher reduction potentials prefer to be reduced, while those with lower reduction potentials prefer to be oxidized.
02

Refer to a standard reduction potential table

The following standard reduction potentials are taken from a standard reduction potential table: \(\mathrm{Br}_2/ \mathrm{Br}^-\): +1.087 V \(\mathrm{H_2/ H}^+\): 0 V \(\mathrm{La^{3+}/La}\): -2.52 V \(\mathrm{Ca/Ca}^{2+}\): -2.87 V \(\mathrm{Cd/Cd}^{2+}\): -0.40 V \(\mathrm{MnO}_4^-/\mathrm{Mn}^{2+}\): +1.51 V (in acidic conditions) \(\mathrm{Zn/Zn}^{2+}\): -0.76 V
03

Identify the strongest oxidizing agent

The strongest oxidizing agent has the highest reduction potential since these species gain electrons most readily. Comparing the reduction potentials listed above, \(\mathrm{Br}_2\) has the highest value of +1.087 V. Therefore, \(\mathrm{Br}_2\) is the strongest oxidizing agent.
04

Identify the strongest reducing agent

The strongest reducing agent has the lowest reduction potential since these species lose electrons most readily. Comparing the reduction potentials listed above, \(\mathrm{Ca}\) has the lowest value of -2.87 V. Therefore, \(\mathrm{Ca}\) is the strongest reducing agent.
05

Identify species that can be oxidized by \(\mathrm{MnO}_{4}^{-}\) in acid

For a reaction to occur, the reduction potential of the oxidizing agent has to be greater than that of the reducing agent. Given that the reduction potential for \(\mathrm{MnO}_4^-\) in acid is +1.51 V, any species with a smaller reduction potential can be oxidized. From the table, the species that can be oxidized are: \(\mathrm{H_2}, \mathrm{La}, \mathrm{Ca}, \mathrm{Cd}, \mathrm{Zn}\)
06

Identify species that can be reduced by \(\mathrm{Zn}(s)\)

For a reaction to occur, the reduction potential of the oxidizing agent has to be greater than that of the reducing agent. Given that the reduction potential for \(\mathrm{Zn}\) is -0.76 V, any species with a larger reduction potential can be reduced. From the table, the species that can be reduced are: \(\mathrm{Br}_2, \mathrm{H_2}, \mathrm{Cd}\) To summarize, the answers to the questions are: a) Strongest oxidizing agent: \(\mathrm{Br}_{2}\) b) Strongest reducing agent: \(\mathrm{Ca}\) c) Species that can be oxidized by \(\mathrm{MnO}_{4}^{-}\) in acid: \(\mathrm{H_2}, \mathrm{La}, \mathrm{Ca}, \mathrm{Cd}, \mathrm{Zn}\) d) Species that can be reduced by \(\mathrm{Zn}(s) :\) \(\mathrm{Br}_2, \mathrm{H}_2, \mathrm{Cd}\)

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Oxidizing Agent
An oxidizing agent is a substance that gains electrons during a chemical reaction. It facilitates the oxidation of another species by accepting electrons from it.
This means that the oxidizing agent itself gets reduced.
  • The strength of an oxidizing agent is measured by its reduction potential.
  • A higher reduction potential indicates a stronger tendency to gain electrons.
In the given exercise, \(\text{Br}_2\), with its reduction potential of \(+1.087\, \text{V}\), is identified as the strongest oxidizing agent. It has the highest ability to accept electrons among the substances listed.
Reducing Agent
The reducing agent is the species that donates electrons in a chemical reaction. It undergoes oxidation by losing electrons when it reduces another molecule, atom, or ion.
This process is critical in redox reactions.
  • Reducing agents have lower reduction potentials.
  • A negative potential suggests a strong ability to donate electrons.
In this exercise, \(\text{Ca}\) shows the lowest reduction potential \((-2.87\, \text{V})\), making it the strongest reducing agent, eager to lose electrons and thus reduce other species.
Redox Reactions
Redox Reactions, short for reduction-oxidation reactions, involve the transfer of electrons between two species.
These reactions are essential for many processes in chemistry and biology.
  • Reduction refers to the gain of electrons.
  • Oxidation refers to the loss of electrons.
  • Every redox reaction involves both an oxidizing agent and a reducing agent.
For example, when \(\text{MnO}_4^-\) oxidizes \(\text{H}_2\), \(\text{H}_2\) loses electrons while \(\text{MnO}_4^-\) gains electrons, demonstrating the redox nature.
Standard Conditions
Standard conditions in chemistry refer to a set of specified conditions for experimental measurements.
These conditions provide a benchmark to compare various properties like reduction potentials.
  • Standard conditions typically mean a pressure of 1 atm.
  • Solutions are at a concentration of 1 M.
  • Temperature is generally set at 298 K (25掳C).
By assuming standard conditions, chemists can ensure that data from different experiments are comparable.
Standard Reduction Potential Table
The Standard Reduction Potential Table is a valuable reference that lists the potential of various half-reactions under standard conditions.
These values predict the direction of redox reactions.
  • Positive values indicate species that are good oxidizing agents.
  • Negative values suggest strong reducing agents.
  • By comparing potentials, one can determine which species will act as an oxidizing or reducing agent.
The table's values are crucial to understanding which substances can undergo oxidation or reduction in combination with others, as seen with \(\text{Br}_2\) and \(\text{Ca}\) in the exercise.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

An electrochemical cell consists of a nickel metal electrode immersed in a solution with \(\left[\mathrm{Ni}^{2+}\right]=1.0 M\) separated by a porous disk from an aluminum metal electrode. a. What is the potential of this cell at \(25^{\circ} \mathrm{C}\) if the aluminum electrode is placed in a solution in which \(\left[\mathrm{Al}^{3+}\right]=7.2 \times 10^{-3} M?\) b. When the aluminum electrode is placed in a certain solution in which \(\left[\mathrm{Al}^{3+}\right]\) is unknown, the measured cell potential at \(25^{\circ} \mathrm{C}\) is 1.62 \(\mathrm{V}\) . Calculate \(\left[\mathrm{Al}^{3+}\right]\) in the unknown solution. (Assume Al is oxidized.)

An electrochemical cell consists of a silver metal electrode immersed in a solution with \(\left[\mathrm{Ag}^{+}\right]=1.00 M\) separated by a porous disk from a compartment with a copper metal electrode immersed in a solution of 10.00\(M \mathrm{NH}_{3}\) that also contains \(2.4 \times 10^{-3} \mathrm{M} \mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}^{2+} .\) The equilibrium between \(\mathrm{Cu}^{2+}\) and \(\mathrm{NH}_{3}\) is: $$\mathrm{Cu}^{2+}(\mathrm{aq})+4 \mathrm{NH}_{3}(\mathrm{aq}) \rightleftharpoons \mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}^{2+}(\mathrm{aq}) \qquad K=1.0 \times 10^{13}$$ and the two cell half-reactions are: $$\begin{array}{rl}{\mathrm{Ag}^{+}+\mathrm{e}^{-} \longrightarrow \mathrm{Ag}} & {\mathscr{E}^{\circ}=0.80 \mathrm{V}} \\ {\mathrm{Cu}^{2+}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Cu}} & {\mathscr{E}^{\circ}=0.34 \mathrm{V}}\end{array}$$ Assuming \(\mathrm{Ag}^{+}\) is reduced, what is the cell potential at \(25^{\circ} \mathrm{C} ?\)

Under standard conditions, what reaction occurs, if any, when each of the following operations is performed? a. Crystals of \(\mathrm{I}_{2}\) are added to a solution of \(\mathrm{NaCl}\) . b. \(\mathrm{Cl}_{2}\) gas is bubbled into a solution of \(\mathrm{Nal}\). c. A silver wire is placed in a solution of \(\mathrm{CuCl}_{2}\) d. An acidic solution of \(\mathrm{FeSO}_{4}\) is exposed to air. For the reactions that occur, write a balanced equation and calculate \(\mathscr{E}^{\circ}, \Delta G^{\circ},\) and \(K\) at \(25^{\circ} \mathrm{C}\)

The ultimate electron acceptor in the respiration process is molecular oxygen. Electron transfer through the respiratory chain takes place through a complex series of oxidationreduction reactions. Some of the electron transport steps use iron-containing proteins called \(c y\) tochromes. All cytochromes transport electrons by converting the iron in the cytochromes from the +3 to the +2 oxidation state. Consider the following reduction potentials for three different cytochromes used in the transfer process of electrons to oxygen (the potentials have been corrected for \(\mathrm{pH}\) and for temperature): cytochrome \(\mathrm{a}\left(\mathrm{Fe}^{3+}\right)+\mathrm{e}^{-} \longrightarrow\) cytochrome \(\mathrm{a}\left(\mathrm{Fe}^{2+}\right)\) $$ \begin{array}{c}\mathscr{C}=0.385 \mathrm{~V}\end{array} $$ cytochrome \(\mathrm{b}\left(\mathrm{Fe}^{3+}\right)+\mathrm{e}^{-} \longrightarrow\) cytochrome \(\mathrm{b}\left(\mathrm{Fe}^{2+}\right)\) $$ \begin{array}{l}\mathscr{E}=0.030 \mathrm{~V}\end{array} $$ cytochrome \(\mathrm{c}\left(\mathrm{Fe}^{3+}\right)+\mathrm{e}^{-} \longrightarrow \mathrm{cytochrome} \mathrm{c}\left(\mathrm{Fe}^{2+}\right)\) $$ \begin{array}{c}\mathscr{C}=0.254 \mathrm{~V}\end{array} $$ In the electron transfer series, electrons are transferred from one cytochrome to another. Using this information, determine the cytochrome order necessary for spontaneous transport of electrons from one cytochrome to another, which eventually will lead to electron transfer to \(\mathrm{O}_{2}\).

What reactions take place at the cathode and the anode when each of the following is electrolyzed? a. molten \(\mathrm{NiBr}_{2} \quad\) b. molten \(\mathrm{AlF}_{3} \quad\) c. molten \(\mathrm{MgI}_{2}\)
See all solutions

Recommended explanations on Chemistry Textbooks

Chemical Analysis

Read Explanation

Making Measurements

Read Explanation

Chemistry Branches

Read Explanation

Nuclear Chemistry

Read Explanation

Physical Chemistry

Read Explanation

Inorganic Chemistry

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.