Question 1

Cathodic protection is attaching a more active metal to the protected metal.

Accepted Answer

Cathodic protection involves using a more active metal (such as zinc) to protect a less active metal (such as steel) from corrosion. The more active metal becomes the anode and corrodes in place of the protected metal, thereby preventing corrosion of the protected metal.

Question 2

Choose the INCORRECT statement.

Accepted Answer

Reversing a half reaction makes it an oxidation potential, not a reduction potential.

Question 3

The active metal is called a sacrificial cathode.

Accepted Answer

The active metal is called a sacrificial anode, not cathode, because it corrodes or sacrifices itself to protect another metal from corrosion.

Question 4

Choose the INCORRECT statement.

Accepted Answer

Electrolytic cells are cells where electron flow is caused by non-spontaneous reactions driven by an external voltage source, not spontaneous reactions.

Question 5

In a galvanic cell, oxidation occurs at the cathode.

Accepted Answer

In a galvanic cell, oxidation occurs at the anode and reduction occurs at the cathode.

Question 6

When Ecell < 0, the reaction is spontaneous.

Accepted Answer

When Ecell < 0, the reaction is not spontaneous. It requires an external source of energy to drive the reaction in the forward direction.

Question 7

A primary battery is recharged by passing electricity through the battery.

Accepted Answer

A primary battery is designed to be used until its chemicals are depleted, at which point it must be disposed of. It cannot be recharged by passing electricity through it.

Question 8

Corrosion of metals is an oxidation-reduction process.

Accepted Answer

Corrosion of metals involves the metal oxidizing (losing electrons) and a reducing agent (such as oxygen) gaining electrons, making it an oxidation-reduction (redox) process.

Question 9

Primary batteries' cell reactions cannot be reversed.

Accepted Answer

Primary batteries are designed for one-time use only and their cell reactions cannot be reversed, meaning they cannot be recharged.

Question 10

In the electrolysis of water, oxygen is evolved at the cathode.

Accepted Answer

Oxygen is evolved at the anode in the electrolysis of water, and hydrogen is evolved at the cathode.

Question 11

Choose the INCORRECT statement.

Accepted Answer

An electrochemical cell consists of two half cells. Each half cell contains an electrode and a solution of its ions. Therefore, statement C is incorrect.

Question 12

Choose the INCORRECT statement.

Accepted Answer

SHE actually stands for Standard Hydrogen Electrodes, not Standard Helium Electrodes.

Question 13

In a galvanic cell, oxidation occurs at the:

Accepted Answer

In a galvanic cell, the anode is the electrode where oxidation takes place.

Question 14

Choose the INCORRECT statement.

Accepted Answer

A strip of metal in a solution of ions of that metal is not an electrode potential, but rather a half-cell. An electrode potential is the measure of the tendency of an electrode to lose or gain electrons when it is connected to a half-cell.

Question 15

In a zinc-lead cell the reaction is: Pb²⁺ + Zn → Pb + Zn²⁺ E° = 0.637 V Which of the following statements about this cell is FALSE?

Accepted Answer

The answer of In a zinc-lead cell the reaction is:...

Question 16

E°cell is the standard cell potential.

Accepted Answer

E°cell is indeed the standard cell potential which measures the voltage or electromotive force (EMF) of an electrochemical cell under standard conditions.

Question 17

Choose the correct statement based on the following oxidation potentials. Mg/Mg²⁺ +2.37 v Fe/Fe²⁺ +0.44 v Cu/Cu²⁺ -0.34 v Zn/Zn²⁺ +0.76 v Sn/Sn²⁺ +0.14 v Ag/Ag⁺ -0.80 v

Accepted Answer

Fe has a positive oxidation potential of +0.44 V, which means it can displace H⁺ from solution, as it is more likely to be oxidized than hydrogen.

Question 18

The hydrogen standard electrode is the most convenient standard electrode to use.

Accepted Answer

The hydrogen standard electrode, while widely used as a reference, is not the most convenient due to the practical difficulties in maintaining the required conditions of pure hydrogen gas and a 1M H+ ion concentration. Other electrodes, like the silver/silver chloride electrode, are often considered more convenient for practical use.

Question 19

The Ecell for the following concentration cell at 25°C is 0.006. Pt ∣ H₂ (g, 0.025 atm) ∣ H⁺(0.012 M) = H⁺ (1 M) ∣ H₂ (g, 1 atm) ∣ Pt 2 H⁺(aq) + 2 e- → H₂(g) E° = 0. V

Accepted Answer

The answer of The Ecell for the following concentration cell...

Question 20

Choose the INCORRECT statement.

Accepted Answer

Half cells in a cell diagram are separated by a double vertical line.

Quiz 20: Electrochemistry

Cathodic protection is attaching a more active metal to the protected metal.

Choose the INCORRECT statement.

The active metal is called a sacrificial cathode.

Choose the INCORRECT statement.

In a galvanic cell, oxidation occurs at the cathode.

When Ecell < 0, the reaction is spontaneous.

A primary battery is recharged by passing electricity through the battery.

Corrosion of metals is an oxidation-reduction process.

Primary batteries' cell reactions cannot be reversed.

In the electrolysis of water, oxygen is evolved at the cathode.

Choose the INCORRECT statement.

Choose the INCORRECT statement.

In a galvanic cell, oxidation occurs at the:

Choose the INCORRECT statement.

In a zinc-lead cell the reaction is: Pb2+ + Zn → Pb + Zn2+ E° = 0.637 V Which of the following statements about this cell is FALSE?

E°cell is the standard cell potential.

Choose the correct statement based on the following oxidation potentials. Mg/Mg2+ +2.37 v Fe/Fe2+ +0.44 v Cu/Cu2+ -0.34 v Zn/Zn2+ +0.76 v Sn/Sn2+ +0.14 v Ag/Ag+ -0.80 v

The hydrogen standard electrode is the most convenient standard electrode to use.

The Ecell for the following concentration cell at 25°C is 0.006. Pt ∣ H2 (g, 0.025 atm) ∣ H+ (0.012 M) = H+ (1 M) ∣ H2 (g, 1 atm) ∣ Pt 2 H+(aq) + 2 e- → H2(g) E° = 0. V

Choose the INCORRECT statement.

In a zinc-lead cell the reaction is: Pb²⁺ + Zn → Pb + Zn²⁺ E° = 0.637 V Which of the following statements about this cell is FALSE?

Choose the correct statement based on the following oxidation potentials. Mg/Mg²⁺ +2.37 v Fe/Fe²⁺ +0.44 v Cu/Cu²⁺ -0.34 v Zn/Zn²⁺ +0.76 v Sn/Sn²⁺ +0.14 v Ag/Ag⁺ -0.80 v

The Ecell for the following concentration cell at 25°C is 0.006. Pt ∣ H₂ (g, 0.025 atm) ∣ H⁺(0.012 M) = H⁺ (1 M) ∣ H₂ (g, 1 atm) ∣ Pt 2 H⁺(aq) + 2 e- → H₂(g) E° = 0. V