New Semester
Started
Get
50% OFF
Study Help!
--h --m --s
Claim Now
Question Answers
Textbooks
Find textbooks, questions and answers
Oops, something went wrong!
Change your search query and then try again
S
Books
FREE
Study Help
Expert Questions
Accounting
General Management
Mathematics
Finance
Organizational Behaviour
Law
Physics
Operating System
Management Leadership
Sociology
Programming
Marketing
Database
Computer Network
Economics
Textbooks Solutions
Accounting
Managerial Accounting
Management Leadership
Cost Accounting
Statistics
Business Law
Corporate Finance
Finance
Economics
Auditing
Tutors
Online Tutors
Find a Tutor
Hire a Tutor
Become a Tutor
AI Tutor
AI Study Planner
NEW
Sell Books
Search
Search
Sign In
Register
study help
engineering
chemical engineering
Chemistry The Central Science 12th edition Theodore Brown, Eugene LeMay, Bruce Bursten, Catherine Murphy, Patrick Woodward - Solutions
(a) Write the half-reaction that occurs at a hydrogen electrode in acidic aqueous solution when it serves as the cathode of a voltaic cell. (b) What is standard about the standard hydrogen electrode? (c) What is the role of the platinum foil in a standard hydrogen electrode?
(a) Write the half-reaction that occurs at a hydrogen electrode in acidic aqueous solution when it serves as the anode of a voltaic cell. (b) The platinum electrode in a standard hydrogen electrode is specially prepared to have a large surface area. Why is this important? (c) Sketch a standard
(a) What is a standard reduction potential? (b) What is the standard reduction potential of a standard hydrogen electrode?
(a) Why is it impossible to measure the standard reduction potential of a single half-reaction? (b) Describe how the standard reduction potential of a half-reaction can be determined.
A voltaic cell that uses the reaction Tl3+(aq) + 2 Cr2+(aq) → Tl+(aq) + 2 Cr3+(aq) has a measured standard cell potential of + 1.19 V. (a) Write the two half-cell reactions. (b) By using data from Appendix E, determine E°red for the reduction of TI3+ (aq) to TI+ (aq). (c) Sketch the voltaic
A voltaic cell that uses the reaction PdCl42-(aq) + Cd(s) → Pd(s) + 4 Cl- (aq) + Cd2+ (aq) has a measured standard cell potential of + 1.03 V. (a) Write the two half-cell reactions. (b) By using data from Appendix E, determine E°red for the reaction involving Pd. (c) Sketch the voltaic cell,
Using standard reduction potentials (Appendix E), calculate the standard emf for each of the following reactions: (a) Cl2(g) + 2 I- (aq) → 2 Cl- (aq) + I2(s) (b) Ni(s) + 2 Ce4+(aq) → Ni2+(aq) + 2 Ce3+(aq) (c) Fe(s) + 2 Fe3+ (aq) → 3 Fe2+ (aq) (d) 2 NO3- (aq) + 8 H+(aq) + 3 Cu(s) → 2 NO(g) +
Using data in Appendix E, calculate the standard emf for each of the following reactions:(a) H2(g) + F2(g) → 2 H+ (aq) + 2 F- (aq)(b) Cu2+(aq) + Ca(s) → Cu(s) + Ca2+ (aq)(c) 3 Fe2+ (aq) → Fe(s) + 2 Fe3+ (aq)(d) 2 ClO3- (aq) + 10 Br- (aq) + 12 H+ (aq) → Cl2(g) + 5 Br2(l) + 6 H2O(l)
The standard reduction potentials of the following half-reactions are given in Appendix E:(a) Determine which combination of these half-cell reactions leads to the cell reaction with the largest positive cell potential and calculate the value. (b) Determine which combination of these half-cell
Assume that you want to construct a voltaic cell that uses the following half-reactions:You begin with the incomplete cell pictured here in which the electrodes are immersed in water. (a) What additions must you make to the cell for it to generate a standard emf? (b) Which electrode functions as
Given the following half-reactions and associated standard reduction potentials:(a) Write the equation for the combination of these half-cell reactions that leads to the largest positive emf and calculate the value.(b) Write the equation for the combination of halfcell reactions that leads to the
A 1 M solution of Cu(NO3)2 is placed in a beaker with a strip of Cu metal. A 1 M solution of SnSO4 is placed in a second beaker with a strip of Sn metal. A salt bridge connects the two beakers, and wires to a voltmeter link the two metal electrodes. (a) Which electrode serves as the anode and which
A voltaic cell consists of a strip of cadmium metal in a solution of Cd(NO3)2 in one beaker, and in the other beaker a platinum electrode is immersed in a NaCl solution, with Cl2 gas bubbled around the electrode. A salt bridge connects the two beakers. (a) Which electrode serves as the anode and
From each of the following pairs of substances, use data in Appendix E to choose the one that is the stronger reducing agent: (a) Fe(s) or Mg(s) (b) Ca(s) or Al(s)
From each of the following pairs of substances, use data in Appendix E to choose the one that is the stronger oxidizing agent: (a) Cl2(g) or Br2(l) (b) Zn2+ (aq) or Cd2+ (aq) (c) CI-(aq) or CIO3- (aq) (d) H2O2(aq) or O3(g)
By using the data in Appendix E, determine whether each of the following substances is likely to serve as an oxidant or a reductant: (a) CI2(g)
Is each of the following substances likely to serve as an oxidant or a reductant: (a) Ce3+ (aq) (b) Ca(s) (c) CIO3- (aq) (d) N2O5(g)?
(a) Assuming standard conditions, arrange the following in order of increasing strength as oxidizing agents in acidic solution: Cr2O72-, H2O2, Cu2+, Cl2, O2. (b) Arrange the following in order of increasing strength as reducing agents in acidic solution: Zn, I-, Sn2+, H2O2, Al.
Based on the data in Appendix E
The standard reduction potential for the reduction of Eu3+ (aq) to Eu2+ (aq) is -0.43V.Using Appendix E, which of the following substances is capable of reducing Eu3+ (aq) to Eu2+ (aq) under standard conditions: Al, Co, H2O2, N2H5+, H2C2O4?
For a spontaneous reaction A(aq) + B(aq) → A- (aq) + B+ (aq), answer the following questions: (a) If you made a voltaic cell out of this reaction, what half-reaction would be occurring at the cathode, and what half-reaction would be occurring at the anode? (b) Which half-reaction from (a) is
The standard reduction potential for the reduction of RuO4 - (aq) to RuO42- is + 0.59 V. By using Appendix E, which of the following substances can oxidize RuO42- (aq) to RuO4- (aq) under standard conditions: Br2(l), BrO3- (aq), Mn2+(aq), O2(g), Sn2+(aq)?
Given the following reduction half-reactions:(a) Write balanced chemical equations for the oxidation of Fe2+(aq) by S2O62- (aq), by N2O(aq), and by VO2+(aq). (b) Calculate ÎG° for each reaction at 298 K. (c) Calculate the equilibrium constant K for each reaction at 298 K.
For each of the following reactions, write a balanced equation, calculate the standard emf, calculate ΔG° at 298 K, and calculate the equilibrium constant K at 298 K. (a) Aqueous iodide ion is oxidized to I2(s) by Hg22+.
If the equilibrium constant for a two-electron redox reaction at 298 K is 1.5 × 10-4, calculate the corresponding ΔG° and E°red.
If the equilibrium constant for a one-electron redox reaction at 298 K is 8.7 × 104, calculate the corresponding ΔG° and E°red.
Using the standard reduction potentials listed in Appendix E, calculate the equilibrium constant for each of the following reactions at 298 K: (a) Fe(s) + Ni2+(aq) → Fe2+ (aq) + Ni(s) (b) Co(s) + 2 H+ (aq) → Co2+(aq) + H2(g) (c) 10 Br- (aq) + 2 MnO4- (aq) + 16 H+(aq) → 2 Mn2+(aq) + 8 H2O(l) +
Using the standard reduction potentials listed in Appendix E, calculate the equilibrium constant for each of the following reactions at 298 K: (a) Cu(s) + 2 Ag+ (aq) → Cu2+ (aq) + 2 Ag(s) (b) 3 Ce4+ (aq) + Bi(s) + H2O(l) → 3 Ce3+ (aq) + BiO+ (aq) + 2 H+ (aq) (c) N2H5 + (aq) + 4 Fe(CN)6 3- (aq)
A cell has a standard cell potential of +0.177 V at 298 K. What is the value of the equilibrium constant for the reaction (a) If n = 1? (b) If n = 2? (c) If n = 3?
At 298 K a cell reaction has a standard cell potential of +0.17 V. The equilibrium constant for the reaction is 5.5 × 105. What is the value of n for the reaction?
A voltaic cell is based on the reaction Sn(s) + I2(s) → Sn2+ (aq) + 2 I- (aq) Under standard conditions, what is the maximum electrical work, in joules, that the cell can accomplish if 75.0 g of Sn is consumed?
Consider the following table of standard electrode potentials for a series of hypothetical reactions in aqueous solution: (a) Which substance is the strongest oxidizing agent? Which is weakest? (b) Which substance is the strongest reducing agent? Which is weakest? (c) Which substance(s) can
Consider the voltaic cell illustrated in Figure 20.5, which is based on the cell reaction Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s) Under standard conditions, what is the maximum electrical work, in joules, that the cell can accomplish if 50.0 g of copper is formed?
(a) Under what circumstances is the Nernst equation applicable? (b) What is the numerical value of the reaction quotient, Q, under standard conditions? (c)What happens to the emf of a cell if the concentrations of the reactants are increased?
(a) A voltaic cell is constructed with all reactants and products in their standard states. Will this condition hold as the cell operates? Explain. (b) Can the Nernst equation be used at temperatures other than room temperature? Explain. (c) What happens to the emf of a cell if the concentrations
What is the effect on the emf of the cell shown in Figure 20.9, which has the overall reaction Zn(s) + 2H+ (aq) → Zn2+(aq) + H2(g), for each of the following changes? (a) The pressure of the H2 gas is increased in the cathode half-cell. (b) Zinc nitrate is added to the anode half-cell. (c) Sodium
A voltaic cell utilizes the following reaction: Al(s) + 3 Ag+ (aq) → Al3+(aq) + 3 Ag(s) What is the effect on the cell emf of each of the following changes?
A voltaic cell is constructed that uses the following reaction and operates at 298 K: Zn(s) + Ni2+(aq) → Zn2+(aq) + Ni(s) (a)What is the emf of this cell under standard conditions? (b) What is the emf of this cell when [Ni2+] = 3.00 M and [Zn2+] = 0.100 M? (c) What is the emf of the cell when
A voltaic cell utilizes the following reaction and operates at 298 K: 3 Ce4+(aq) + Cr(s) → 3 Ce3+(aq) + Cr3+(aq) (a) What is the emf of this cell under standard conditions? (b) What is the emf of this cell when [Ce4+] = 3.0 M, [Ce3+] = 0.10 M, and [Cr3+] = 0.010 M? (c) What is the emf of the cell
A voltaic cell utilizes the following reaction: 4 Fe2+(aq) + O2(g) + 4 H+(aq) → 4 Fe3+(aq) + 2 H2 O(l) (a) What is the emf of this cell under standard conditions?
A voltaic cell utilizes the following reaction: 2 Fe3+(aq) + H2(g) → 2 Fe2+(aq) + 2 H+(aq) (a) What is the emf of this cell under standard conditions? (b) What is the emf for this cell when [Fe3+] = 3.50 M, PH2 = 0.95 atm, [Fe2+] = 0.0010 M, and the pH in both half-cells is 4.00?
A voltaic cell is constructed with two Zn2+ - Zn electrodes. The two half-cells have [Zn2+] = 1.8 M and [Zn2+] = 1.00 × 10-2 M, respectively. (a) Which electrode is the anode of the cell? (b) What is the standard emf of the cell? (c) What is the cell emf for the concentrations given? (d) For each
Consider a redox reaction for which E ° is a negative number. (a) What is the sign of ΔG° for the reaction? (b) Will the equilibrium constant for the reaction be larger or smaller than 1? (c) Can an electrochemical cell based on this reaction accomplish work on its surroundings?
A voltaic cell is constructed with two silver-silver chloride electrodes, each of which is based on the following halfreaction: AgCl(s) + e- → Ag(s) + Cl- (aq) The two half-cells have [CI-] = 0.0150 M and [CI-] = 2.55 M, respectively. (a) Which electrode is the cathode of the cell? (b) What is
The cell in Figure 20.9 could be used to provide a measure of the pH in the cathode half-cell. Calculate the pH of the cathode half-cell solution if the cell emf at 298 K is measured to be +0.684 v when [Zn2+] = 0.30 M and PH2 = 0.90 atm.
A voltaic cell is constructed that is based on the following reaction: Sn2+(aq) + Pb(s) → Sn(s) + Pb2+(aq) (a) If the concentration of Sn2+ in the cathode half-cell is 1.00 M and the cell generates an emf of +0.22 V, what is the concentration of Pb2+ in the anode half-cell? (b) If the anode
(a) What happens to the emf of a battery as it is used? Why does this happen? (b) The AA-size and D-size alkaline batteries are both 1.5-V batteries that are based on the same electrode reactions. What is the major difference between the two batteries? What performance feature is most affected by
(a) Suggest an explanation for why liquid water is needed in an alkaline battery. (b) What is the advantage of using highly concentrated or solid reactants in a voltaic cell?
During a period of discharge of a lead-acid battery, 402 g of Pb from the anode is converted into PbSO4(s). (a) What mass of PbO2(s) is reduced at the cathode during this same period? (b) How many coulombs of electrical charge are transferred from Pb to PbO2?
During the discharge of an alkaline battery, 4.50 g of Zn is consumed at the anode of the battery. (a) What mass of MnO2 is reduced at the cathode during this discharge? (b) How many coulombs of electrical charge are transferred from Zn to MnO2?
Heart pacemakers are often powered by lithium-silver chromate "button" batteries. The overall cell reaction is 2 Li(s) + Ag2CrO4(s) → Li2CrO4(s) + 2 Ag(s) (a) Lithium metal is the reactant at one of the electrodes of the battery. Is it the anode or the cathode? (b) Choose the two half-reactions
Mercuric oxide dry-cell batteries are often used where a highenergy density is required, such as in watches and cameras. The two half-cell reactions that occur in the battery are HgO(s) + H2O(l) + 2 e- → Hg(l) + 2 OH- (aq) Zn(s) + 2 OH- (aq) → ZnO(s) + H2O(l) + 2 e- (a) Write the overall cell
(a) Suppose that an alkaline battery was manufactured using cadmium metal rather than zinc. What effect would this have on the cell emf? (b) What environmental advantage is provided by the use of nickel-metal-hydride batteries over nickel-cadmium batteries?
Consider the following voltaic cell:(a) Which electrode is the cathode? (b) How would you determine the standard emf generated by this cell? (c) What is the change in the cell voltage when the ion concentrations in the cathode half-cell are increased by a factor of 10? (d) What is the change in the
(a) The nonrechargeable lithium batteries used for photography use lithium metal as the anode. What advantages might be realized by using lithium rather than zinc, cadmium, lead, or nickel? (b) The rechargeable lithium-ion battery does not use lithium metal as an electrode material. Nevertheless,
The hydrogen-oxygen fuel cell has a standard emf of 1.23 V. What advantages and disadvantages there to using this device as a source of power compared to a 1.55-V alkaline battery?
(a) What is the difference between a battery and a fuel cell? (b) Can the "fuel" of a fuel cell be a solid? Explain.
(a) Write the anode and cathode reactions that cause the corrosion of iron metal to aqueous iron(II). (b) Write the balanced half-reactions involved in the air oxidation of Fe2+ (aq) to Fe2O3 ∙ 3 H2 O.
(a) Based on standard reduction potentials, would you expect copper metal to oxidize under standard conditions in the presence of oxygen and hydrogen ions? (b) When the Statue of Liberty was refurbished, Teflon spacers were placed between the iron skeleton and the copper metal on the surface of the
(a) Magnesium metal is used as a sacrificial anode to protect underground pipes from corrosion. Why is the magnesium referred to as a "sacrificial anode"? (b) Looking in Appendix E, suggest what metal the underground pipes could be made from in order for magnesium to be successful as a sacrificial
An iron object is plated with a coating of cobalt to protect against corrosion. Does the cobalt protect iron by cathodic protection? Explain.
A plumber's handbook states that you should not connect a brass pipe directly to a galvanized steel pipe because electrochemical reactions between the two metals will cause corrosion. The handbook recommends you use instead an insulating fitting to connect them. Brass is a mixture of copper and
A plumber's handbook states that you should not connect a copper pipe directly to a steel pipe because electrochemical reactions between the two metals will cause corrosion. The handbook recommends you use instead an insulating fitting to connect them. What spontaneous redox reaction(s) might cause
(a) What is electrolysis? (b) Are electrolysis reactions thermodynamically spontaneous? Explain. (c) What process occurs at the anode in the electrolysis of molten NaCl?
Consider the half-reaction Ag+(aq) + e- Ag(s).(a) Which of the lines in the following diagram indicates how the reduction potential varies with the concentration of Ag+?(b) What is the value of Ered when log [Ag+] = 0?
(a) What is an electrolytic cell? (b) The negative terminal of a voltage source is connected to an electrode of an electrolytic cell. Is the electrode the anode or the cathode of the cell? Explain. (c) The electrolysis of water is often done with a small amount of sulfuric acid added to the water.
(a) A Cr3+ (aq) solution is electrolyzed, using a current of 7.60 A. What mass of Cr(s) is plated out after 2.00 days? (b) What amperage is required to plate out 0.250 mol Cr from a Cr3+ solution in a period of 8.00 h?
Metallic magnesium can be made by the electrolysis of molten MgCl2. (a) What mass of Mg is formed by passing a current of 4.55 A through molten MgCl2, for 4.50 days? (b) How many minutes are needed to plate out 25.00 g Mg from molten MgCl2 using 3.50 A of current?
(a) Calculate the mass of Li formed by electrolysis of molten LiCl by a current of 7.5 × 104 A flowing for a period of 24 h. Assume the electrolytic cell is 85% efficient.(b) What is the minimum voltage required to drive the reaction?
Elemental calcium is produced by the electrolysis of molten CaCl2.(a) What mass of calcium can be produced by this process if a current of 7.5 × 103 A is applied for 48 h? Assume that the electrolytic cell is 68% efficient.(b) What is the minimum voltage needed to cause the electrolysis?
Metallic gold is collected from below the anode when crude copper metal is refined by electrolysis. Explain this behavior.
The crude copper that is subjected to electrorefining contains tellurium as an impurity. The standard reduction potential between tellurium and its lowest common oxidation state, Te4+, is Te4+(aq) + 4 e- → Te(s) E°red = 0.57 V
A disproportionation reaction is an oxidation-reduction reaction in which the same substance is oxidized and reduced. Complete and balance the following disproportionation reactions:
This oxidation-reduction reaction in acidic solution is spontaneous: 5 Fe2+(aq) + MnO4 -(aq) + 8 H+(aq)¡ 5 Fe3+(aq) + Mn2+(aq) + 4 H2O(l) A solution containing KMnO4 and H2SO4 is poured into one beaker, and a solution of FeSO4 is poured into another. A salt bridge is used to join the beakers. A
A common shorthand way to represent a voltaic cell is
Indicate whether each of the following nuclides lies within the belt of stability in Figure 21.2: (a) neon-24 (b) chlorine-32, (c) tin-108, (d) polonium-216. For any that do not, describe a nuclear decay process that would alter the neutron-to-proton ratio in the direction of increased stability.
Write balanced nuclear equations for the following processes: (a) Rubidium-90 undergoes beta emission (b) Selenium-72 undergoes electron capture (c) Krypton-76 undergoes positron emission (d) Radium-226 emits alpha radiation.
Write balanced nuclear equations for the following transformations: (a) Bismuth-213 undergoes alpha decay (b) Nitrogen-13 undergoes electron capture (c) Technicium-98 undergoes electron capture (d) Gold-188 decays by positron emission.
Decay of which nucleus will lead to the following products: (a) Bismuth-211 by beta decay (b) Chromium-50 by positron emission (c) Tantalum-179 by electron capture (d) Radium- 226 by alpha decay?
What particle is produced during the following decay processes: (a) Sodium-24 decays to magnesium-24 (b) Mercury- 188 decays to gold-188 (c) Iodine-122 decays to xenon-122 (d) plutonium-242 decays to uranium-238?
The naturally occurring radioactive decay series that begins with stops with formation of the stable nucleus. The decays proceed through a series of alpha-particle and beta-particle emissions. How many of each type of emission are involved in this series?
A radioactive decay series that begins with ends with formation of the stable nuclide . How many alphaparticle emissions and how many beta-particle emissions are involved in the sequence of radioactive decays?
Predict the type of radioactive decay process for the following radionuclides:(c) Phosphorus-32,(d) chlorine-39.
Each of the following nuclei undergoes either beta decay or positron emission. Predict the type of emission for each:(c) Iodine-120(d) silver-102.
One of the nuclides in each of the following pairs is radioactive. Predict which is radioactive and which is stable:(b) 209Bi and 208Bi(c) Nickel-58 and nickel-65. Explain.
Write the balanced nuclear equation for the reaction represented by the diagram shown here.
One nuclide in each of these pairs is radioactive. Predict which is radioactive and which is stable:(b) 12C and 14C(c) Lead-206 and thorium-230. Explain your choice in each case.
Which of the following nuclides have magic numbers of both protons and neutrons:(a) Helium-4(b) Oxygen-18(c) Calcium- 40(d) Zinc-66(e) Lead-208?
Despite the similarities in the chemical reactivity of elements in the lanthanide series, their abundances in Earth's crust vary by two orders of magnitude. This graph shows the relative abundance as a function of atomic number. How do you explain the sawtooth variation across the series?
Using the concept of magic numbers, explain why alpha emission is relatively common, but proton emission is nonexistent.
Which of the following nuclides would you expect to be radioactive: tungsten-184, polonium-206? Justify your choices.
Why are nuclear transmutations involving neutrons generally easier to accomplish than those involving protons or alpha particles?
Complete and balance the following nuclear equations by supplying the missing particle:
Complete and balance the following nuclear equations by supplying the missing particle:
Write balanced equations for
Draw a diagram similar to that shown in Exercise 21.2 that illustrates the nuclear reaction
Each statement that follows refers to a comparison between two radioisotopes, A and X. Indicate whether each of the following statements is true or false, and why. (a) If the half-life for A is shorter than the half-life for X, A has a larger decay rate constant. (b) If X is "not radioactive," its
It has been suggested that strontium-90 (generated by nuclear testing) deposited in the hot desert will undergo radioactive decay more rapidly because it will be exposed to much higher average temperatures. (a) Is this a reasonable suggestion? (b) Does the process of radioactive decay have an
Some watch dials are coated with a phosphor, like ZnS, and a polymer in which some of the 1H atoms have been replaced by 1H atoms, tritium. The phosphor emits light when struck by the beta particle from the tritium decay, causing the dials to glow in the dark. The half-life of tritium is 12.3 yr.
It takes 5.2 min for a 1.000-g sample of 210Fr to decay to 0.250 g. What is the half-life of 210Fr?
Showing 4500 - 4600
of 6778
First
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
Last
Step by Step Answers