Q: Which equation correctly relates the standard cell potential $$E^ ext{o}_ ext{cell} to $$the equilibrium constant $$K$$ for a redox reaction at 298 K?

$$E^ ext{o}_ ext{cell} = \frac{0.0592\text{ V}}{n} \log K$$

Q: Which equation correctly relates Gibbs free energy change to cell potential?

$$\Delta G = -nFE^ ext{o}_\text{cell}$$

Q: Which equation would you use to calculate the cell potential for a nonstandard state electrochemical cell at 298 K?

$$E_ ext{cell} = E^ ext{o}_ ext{cell} - \frac{0.0592\text{ V}}{n} \log Q$$

Q: A dry-cell battery uses Zn as the anode and MnO$$_2 as $$the cathode. Which reaction occurs at the anode?

$$\text{Zn}(s) + 2\text{OH}^-(aq) \rightarrow \text{Zn(OH)}_2(s) + 2e^-$$

Question 1

Which equation correctly relates the standard cell potential $$E^	ext{o}_	ext{cell} to $$the equilibrium constant $$K$$ for a redox reaction at 298 K?

Accepted Answer

$$E^	ext{o}_	ext{cell} = \frac{0.0592	ext{ V}}{n} \log K$$

Question 2

A lead-acid battery consists of six cells in series, each producing about 2 V. What is the total voltage output of a fully charged lead-acid battery?

Accepted Answer

12 V

Question 3

Which of the following statements about dry-cell batteries is correct?

Accepted Answer

They use Zn/Mn chemistry and are nonchargeable.

Question 4

What is the purpose of platinum electrodes in electrochemical cells?

Accepted Answer

To provide a non-reactive surface for electron transfer.

Question 5

Which battery type is most likely to catch fire if improperly disposed of?

Accepted Answer

Li-ion battery

Question 6

Given the following half-reactions, which metal is the best reducing agent?

$$	ext{Mg}^{2+} + 2e^- ightarrow 	ext{Mg}(s)\quad E^	ext{o} = -2.37 V$$
$$	ext{Zn}^{2+} + 2e^- ightarrow 	ext{Zn}(s)\quad E^	ext{o} = -0.76 V$$
$$	ext{Cu}^{2+} + 2e^- ightarrow 	ext{Cu}(s)\quad E^	ext{o} = 0.34 V$$

Accepted Answer

Mg

Question 7

Which equation describes the relationship between cell potential and reaction quotient for nonstandard conditions?

Accepted Answer

$$E_	ext{cell} = E^	ext{o}_	ext{cell} - \frac{RT}{nF} \ln Q$$

Question 8

A concentration cell is constructed with two Cu electrodes. One half-cell contains $$[	ext{Cu}^{2+}] = 1.0 M $$and the other $$[	ext{Cu}^{2+}] = 0.010 M. $$What is the direction of electron flow?

Accepted Answer

From the 0.010 M cell to the 1.0 M cell

Question 9

Which battery type uses Ni/metal hydride chemistry and is lighter than NiCad batteries?

Accepted Answer

NiMH battery

Question 10

Which equation correctly relates Gibbs free energy change to cell potential?

Accepted Answer

$$\Delta G = -nFE^	ext{o}_	ext{cell}$$

Question 11

Which of the following is true for a spontaneous electrochemical reaction at standard state?

Accepted Answer

$$\Delta G  0$$, $$K \u003e 1$$

Question 12

Which of the following is a real-life example of a concentration cell?

Accepted Answer

The sodium-potassium pump in nerve cells

Question 13

If $$Q = K in $$the Nernst equation, what is the value of $$E_	ext{cell}$$?

Accepted Answer

$$E_	ext{cell} = 0$$

Question 14

Which battery type is commonly used in breathalyzers and involves the oxidation of ethanol?

Accepted Answer

Fuel cell

Question 15

Which of the following is NOT a feature of NiCad batteries?

Accepted Answer

Nonchargeable

Question 16

Which equation would you use to calculate the cell potential for a nonstandard state electrochemical cell at 298 K?

Accepted Answer

$$E_	ext{cell} = E^	ext{o}_	ext{cell} - \frac{0.0592	ext{ V}}{n} \log Q$$

Question 17

Which of the following is a correct description of an electrolytic cell?

Accepted Answer

Uses electricity to drive nonspontaneous chemical reactions

Question 18

A dry-cell battery uses Zn as the anode and MnO$$_2 as $$the cathode. Which reaction occurs at the anode?

Accepted Answer

$$	ext{Zn}(s) + 2	ext{OH}^-(aq) ightarrow 	ext{Zn(OH)}_2(s) + 2e^-$$

Question 19

Which battery type is commonly used in automobiles and is rechargeable?

Accepted Answer

Lead-acid battery

Electrochemistry and Batteries: Study Notes for General Chemistry

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