1) Which of the following statements is incorrect?
(a) The direction of a redox reaction can only be determined experimentally.
(b) Since voltage depends on concentrations, using standard conditions makes it easier to compare different reactions.
(c) We have to measure the cell potential to obtain the difference in potential energy because the potential of half-reactions cannot be measured directly.
(d) Half-cell potentials for half-reactions are determined by comparing them with a standardized electrode.
2) Which of the following statements is incorrect?
(a) The direction of a redox reaction can be predicted by the sign of the cell potential (E°net).
(b) Since voltage does not depend on concentrations, we use standard conditions to compare different reactions.
(c) We have to measure the cell potential to obtain the difference in potential energy because the potential of half-reactions cannot be measured directly.
(d) Half-cell potentials for half-reactions are determined by comparing them with a standardized electrode.
3) Which of the following statements is incorrect?
(a) The direction of a redox reaction can be predicted by the sign of the cell potential (E°net).
(b) Since voltage depends on concentrations, using standard conditions makes it easier to compare different reactions.
(c) We have to measure the cell potential to obtain the difference in potential energy because the potential of half-reactions cannot be measured directly.
(d) Half-cell potentials for half-reactions are measured directly and summed to determine the cell potential.
4) Which of the following statements is incorrect?
(a) A salt bridge is not required when using the standard hydrogen electrode to measure the potential of another species.
(b) Since voltage depends on concentrations, using standard conditions makes it easier to compare different reactions.
(c) Electrons move from the electrode of higher potential energy to another of lower potential energy because of emf.
(d) If the standard hydrogen cell is paired with a half-cell that is a better oxidizing agent than hydrogen, hydrogen will be oxidized to the hydronium ion.
5) Which of the following statements is incorrect?
(a) Electrons move from the electrode of higher potential energy to another of lower potential energy.
(b) A coulomb is the quantity of charge that passes in an electrical circuit when a current of 1 ampere flows for 1 second.
(c) If a metal is at the anode, it will decrease in mass as the reaction progresses.
(d) If Ered is negative, then the reaction is always reactant favored.
6) Which of the following statements is incorrect?
(a) Electromotive force is the force that causes electron flow.
(b) Standard conditions are that all substances must be pure and in the state in which they exist at 1 bar, gasses must be at a pressure of 1 atm, and solutes at a concentration of 1 M.
(c) The standard hydrogen cell is always the cathode in an electrochemical cell.
(d) A "D" size battery and a "AA" size battery have the same voltage.
7) Which of the following statements is incorrect?
(a) A volt has the dimensions of J/C.
(b) The standard hydrogen electrode must be hooked up to a platinum half-cell for any reaction to occur.
(c) If Enet is positive, then the reaction is always product favored.
(d) If a metal is at the cathode in an electrochemical cell, it will increase in mass as the reaction progresses.
8) Which of the following statements is incorrect?
(a) If a metal species is the anode in an electrochemical cell, it will decrease in mass as the reaction progresses.
(b) The potential of the hydrogen electrode is assigned to be exactly zero.
(c) If the standard hydrogen cell is paired with a half-cell that is a better oxidizing agent, the hydronium ion will be reduced to hydrogen.
(d) Half-cell potentials for half-reactions are determined by comparing the cell potential with a standardized electrode.
9) As you observe the reaction in a voltaic cell, you notice that the tin electrode seems to be disappearing while there are deposits forming on the silver electrode. Which of the following is a correct statement?
(a) The silver electrode is the cathode and the tin electrode is the anode.
(b) Electrons are flowing from the silver electrode to the tin electrode.
(c) Nitrate ions are flowing through the salt bridge to the silver solution.
(d) The half-reaction occurring at the tin electrode is Sn4+ + 2e-
Sn2+.
10) As you observe the reaction in an electrochemical cell, you notice that the aluminum electrode seems to be disappearing while there are deposits forming on the nickel electrode. Which of the following is a correct statement?
(a) The nickel electrode is the cathode and the aluminum electrode is the anode.
(b) Sulfate ions are flowing through the salt bridge to the nickel solution.
(c) The electrons flow from the nickel electrode to the aluminum electrode.
(d) If this cell were used as a battery, the nickel electrode would be marked "-".