Question 1

Which of the following statements best describes the process occurring at the anode in a voltaic cell?

Accepted Answer

Oxidation occurs, electrons are lost by the species at the anode.

Question 2

In the reaction $$\mathrm{Zn(s) + Cu$$^{2+}$$(aq) \rightarrow Zn$$^{2+}$$(aq) + Cu(s)}$$, which species is oxidized and which is reduced?

Accepted Answer

Zn is oxidized, Cu$$^{2+} is $$reduced.

Question 3

Which of the following is the correct oxidation state for oxygen in $$\mathrm{CO_2$}$$?

Accepted Answer

$$-2$$

Question 4

A dry cell battery uses which of the following as its anode?

Accepted Answer

Zinc

Question 5

Which equation correctly relates the standard cell potential ($$E^{\circ}$$_{cell}$$) to the standard free energy change ($$\Delta $$G^{\circ}$$)?

Accepted Answer

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

Question 6

Which of the following best explains why aluminum does not corrode as easily as iron, despite oxidizing faster?

Accepted Answer

Aluminum forms a protective oxide layer that prevents further corrosion.

Question 7

In a hydrogen-oxygen fuel cell, what is the main product of the reaction?

Accepted Answer

Water

Question 8

Which of the following is a method to prevent the rusting of iron pipes buried underground?

Accepted Answer

Attaching a sacrificial electrode made of a more easily oxidized metal.

Question 9

What is the purpose of the salt bridge in a voltaic cell?

Accepted Answer

To allow ions to flow and maintain charge balance between the two half-cells.

Question 10

Which battery type is most commonly used in modern portable electronic devices due to its high energy density?

Accepted Answer

Lithium-ion

Question 11

If the standard reduction potential for $$\mathrm{Ni$$^{2+}$$ + 2e^- \rightarrow Ni} is$$ $$-0.23\ \mathrm{V}$$ and for $$\mathrm{Mn$$^{2+}$$ + 2e^- \rightarrow Mn} is$$ $$-1.18\ \mathrm{V}$$, what is the standard cell potential for the reaction $$\mathrm{Mn(s) + Ni$$^{2+}$$(aq) \rightarrow Mn$$^{2+}$$(aq) + Ni(s)}$$?

Accepted Answer

$$0.95\ \mathrm{V}$$

Question 12

Which of the following is true for a spontaneous electrochemical reaction under standard conditions?

Accepted Answer

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

Question 13

Which equation is used to calculate the cell potential under nonstandard conditions?

Accepted Answer

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

Question 14

Which of the following statements about electrolytic cells is correct?

Accepted Answer

Electrolytic cells use electrical energy to drive nonspontaneous chemical reactions.

Question 15

In the half-reaction method for balancing redox reactions in acidic solution, which step comes immediately after balancing all elements except H and O?

Accepted Answer

Balance O by adding $$\mathrm{H_2O}.$$

Question 16

Which of the following metals would NOT be dissolved by hydrochloric acid based on its standard reduction potential?

Accepted Answer

Copper

Question 17

What is the main advantage of using a lead-acid battery in automobiles?

Accepted Answer

It can deliver high current reliably and is low cost.

Question 18

Which of the following best describes the flow of electrons in a voltaic cell?

Accepted Answer

Electrons flow from the anode to the cathode.

Question 19

Which of the following is a real-world application of electroplating?

Accepted Answer

Coating inexpensive metals with a thin layer of copper for pennies.

Electrochemistry: Redox Reactions, Voltaic Cells, and Applications

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