What is the minimum voltage needed for the electrolytic process shown in Figure 18.19?
Figure 18.19 A diagram showing the electrode reactions during the
Want to see the full answer?
Check out a sample textbook solutionChapter 18 Solutions
Chemistry
- As an example of an electrolytic cell, the text states: Sodium chloride is electrolyzed commercially in an apparatus called the Downs cell to produce sodium and chlorine. This is a high-temperature operation; the electrolyte is molten NaCl. Write the half-reaction equations for the changes taking place at each electrode. Is the electrode at which sodium is produced the anode or the cathode? The Downs cell electrolyzes molten melted sodium chloride, producing sodium and chlorine.arrow_forwardThe voltaic cell is represented as Zn(s)Zn2+(1.0M)Cu2+(1.0M)Cu(s) Which of the following statements is not true of this cell? a The mass of the zinc electrode, Zn(s), decreases as the cell runs. b The copper electrode is the anode. c Electrons flow through the external circuit from the zinc electrode to the copper electrode. d Reduction occurs at the copper electrode as the cell runs. e The concentration of Cu2+ decreases as the cell runs.arrow_forwardThe mass of three different metal electrodes, each from a different galvanic cell, were determined before and after the current generated by the oxidation-reduction reaction in each cell was allowed to flow for a few minutes. The first metal electrode, given the label A, was found to have increased in mass; the second metal electrode, given the label B, did not change in mass; and the third metal electrode, given the label C, was found to have lost mass. Make an educated guess as to which electrodes were active and which were inert electrodes, and which were anode(s) and which were the cathode(s).arrow_forward
- Identify each statement as true or false. Rewrite each false statement to make it true. (a) Oxidation always occurs at the anode of an electrochemical cell. (b) The anode of a discharging voltaic cell is the site ofreduction and is negative. (c) Standard-state conditions for electrochemical cells are aconcentration of 1.0 M for dissolved species and a pressure of 1 bar for gases. (d) The potential of a voltaic cell does not change withtemperature. (e) All product-favored oxidation-reduction reactions have astandard cell potential Ecell, with a negative sign.arrow_forwardA voltaic cell is constructed in which one half-cell consists of a silver wire in an aqueous solution of AgNO3.The other half cell consists of an inert platinum wire in an aqueous solution containing Fe2+(aq) and Fe3+(aq). (a) Calculate the cell potential, assuming standard conditions. (b) Write the net ionic equation for the reaction occurring in the cell. (c) Which electrode is the anode and which is the cathode? (d) If [Ag+] is 0.10 M, and [Fe2+] and [Fe3+] are both 1.0 M, what is the cell potential? Is the net cell reaction still that used in part (a)? If not, what is the net reaction under the new conditions?arrow_forwardElectrochemical Cells II Consider this cell running under standard conditions: Ni(s)Ni2(aq)Cu+(aq)Cu(s) a Is this cell a voltaic or an electrolytic cell? How do you know? b Does current flow in this cell spontaneously? c What is the maximum cell potential for this cell? d Say the cell is connected to a voltmeter. Describe what you might see for an initial voltage and what voltage changes, if any, you would observe as time went by. e What is the free energy of this cell when it is first constructed? f Does the free energy of the cell change over time as the cell runs? If so, how does it change?arrow_forward
- Consider the following cell running under standard conditions: Fe(s)Fe2+(aq)Al3+(aq)Al(s) a Is this a voltaic cell? b Which species is being reduced during the chemical reaction? c Which species is the oxidizing agent? d What happens to the concentration of Fe3+(aq) as the reaction proceeds? e How does the mass of Al(s) change as the reaction proceeds?arrow_forwardAn aqueous solution of an unknown salt of gold is electrolyzed by a current of 2.75 amps for 3.39 hours. The electroplating is carried out with an efficiency of 93.0%, resulting in a deposit of 21.221 g of gold. a How many faradays are required to deposit the gold? b What is the charge on the gold ions (based on your calculations)?arrow_forwardA solution of copper(II) sulfate is electrolyzed by passing a current through the solution using inert electrodes. Consequently, there is a decrease in the Cu2+ concentration and an increase in the hydronium ion concentration. Also, one electrode increases in mass and a gas evolves at the other electrode. Write half-reactions that occur at the anode and at the cathode.arrow_forward
- A potassium chloride solution is electrolyzed by passing a current through the solution using inert electrodes. A gas evolves at each electrode, and there is a large increase in pH of the solution. Write the half-reactions that occur at the anode and at the cathode.arrow_forwardGalvanized steel pipes are used in the plumbing of many older homes. When copper plumbing is added to a system consisting of galvanized steel pipes it is necessary to place an insulator between the copper and the steel to avoid corrosion. Write a balanced oxidation-reduction equation for the reaction that occurs if the pipes are directly connected. What is the standard potential between the metals?arrow_forwardYou have 1.0 M solutions of Al(NO3)3 and AgNO3 along with Al and Ag electrodes to construct a voltaic cell. The salt bridge contains a saturated solution of KCl. Complete the picture associated with this problem by a writing the symbols of the elements and ions in the appropriate areas (both solutions and electrodes). b identifying the anode and cathode. c indicating the direction of electron flow through the external circuit. d indicating the cell potential (assume standard conditions, with no current flowing). e writing the appropriate half-reaction under each of the containers. f indicating the direction of ion flow in the salt bridge. g identifying the species undergoing oxidation and reduction. h writing the balanced overall reaction for the cell.arrow_forward
- General Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage LearningChemistry: Principles and PracticeChemistryISBN:9780534420123Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward MercerPublisher:Cengage Learning
- Chemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningChemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage LearningPrinciples of Modern ChemistryChemistryISBN:9781305079113Author:David W. Oxtoby, H. Pat Gillis, Laurie J. ButlerPublisher:Cengage Learning