Question 1

Which of the following substances is the oxidizing agent in the chemical reaction ? 2CO + 2NO → 2CO₂ + N₂

Accepted Answer

In this chemical reaction, NO is being reduced from a +2 oxidation state to a 0 oxidation state, meaning it is gaining electrons and being reduced. Therefore, the other substance it is reacting with (in this case, CO) must be the oxidizing agent, as it is giving away electrons and being oxidized.

Question 2

Rust formation is accelerated in the presence of salt water because_____.

Accepted Answer

Salt water conducts electricity, which facilitates the flow of electrons during the electrochemical process of rust formation, thereby accelerating it.

Question 3

Which substance is the reducing agent in this redox equation? HF + Cl₂ → F₂ + HCl

Accepted Answer

In the given redox equation, HF is losing electrons (being oxidized) to form F₂. Thus, HF is the reducing agent, which means that it is the substance that is undergoing oxidation and causing another substance to be reduced.

Question 4

Which of these occur(s) during oxidation?
I. Gaining electrons
II. Losing hydrogen
III. Losing oxygen

Accepted Answer

Oxidation involves losing electrons or hydrogen, not gaining electrons or losing oxygen.

Question 5

Which of these occur(s) during reduction?
I. Losing electrons
II. Gaining hydrogen
III. Losing oxygen

Accepted Answer

Reduction involves gaining hydrogen or losing oxygen, not losing electrons. Losing electrons is associated with oxidation.

Question 6

Which of these statements about redox reactions is incorrect ?

Accepted Answer

Oxidation is not always the loss of oxygen. It is the loss of electrons or an increase in oxidation state.

Question 7

Which substance is the oxidizing agent in this redox reaction? Br⁻(aq) + MnO₄⁻(aq) → Br₂(l) + Mn²⁺(aq)

Accepted Answer

In this redox reaction, the species that is reduced is , which is gaining electrons. Therefore, the oxidizing agent is the species that is being reduced, which is MnO₄^.

Question 8

Which of these occur(s) during oxidation?

Accepted Answer

Oxidation involves losing electrons or gaining oxygen, which is not described by any of the options provided.

Question 9

Which of these is a redox process?
I. Rusting of iron
II. Respiration
III. Burning hydrocarbons

Accepted Answer

All three processes involve the transfer of electrons. Rusting of iron involves the reduction of oxygen and the oxidation of iron, respiration involves the transfer of electrons in the breakdown of glucose to produce energy, and burning hydrocarbons involves the oxidation of carbon compounds to produce carbon dioxide and water.

Question 10

Which of the following substances is the oxidizing agent in the chemical reaction ? PbCl₄ + SnCl₂ → PbCl₂ + SnCl₄

Accepted Answer

PbCl2 acts as the oxidizing agent because it gains electrons (reduces) when it goes from PbCl2 to PbCl4, while Sn goes from SnCl2 to SnCl4, losing electrons (oxidizes), making Sn the reducing agent.

Question 11

Redox reactions involve the transfer of _____.

Accepted Answer

Redox reactions involve the transfer of electrons from one molecule to another. The molecule that loses electrons is oxidized, while the molecule that gains electrons is reduced.

Question 12

Which of these is not an application of oxidizing agents?

Accepted Answer

Metal processing involves reducing agents, not oxidizing agents.

Question 13

Which of these occurs(s) during reduction?

Accepted Answer

Reduction involves either gaining electrons or gaining hydrogen (which usually involves gaining electrons as well), and often results in a molecule losing oxygen (which is why reduction is sometimes called "de-oxidation"). Therefore, all of the choices (A, B, and C) are correct.

Question 14

Which substance is oxidized in this redox reaction? Br⁻(aq) + MnO₄⁻(aq) → Br₂(l) + Mn²⁺(aq)

Accepted Answer

Br^- is oxidized as it goes from an oxidation state of -1 in Br^- to 0 in Br2.

Question 15

Which of these is not an oxidation-reduction reaction?

Accepted Answer

This is a acid-base reaction, not an oxidation-reduction reaction.

Question 16

Which of these pairs is correctly matched?

Accepted Answer

In oxidation reactions, there is a loss of electrons, not necessarily oxygen. Reduction reactions involve gaining electrons. Therefore, choice C is the correct pairing.

Question 17

During oxidation-reduction reactions, the substance that loses electrons is _____and the substance that gains electrons is _____.

Accepted Answer

In oxidation-reduction reactions, there is a transfer of electrons between two species. The species that loses electrons is undergoing oxidation (hence, it is being oxidized) and the species that gains electrons is being reduced. Therefore, the correct answer is A) oxidized; reduced.

Question 18

Which of these statements about redox reactions is incorrect ?

Accepted Answer

Oxidation is not the gain of hydrogen; it is the loss of hydrogen. The gain of hydrogen is associated with reduction.

Question 19

Which of these substances is the most common oxidizing agent?

Accepted Answer

Oxygen (O) is the most common oxidizing agent, and option C contains molecular oxygen (O2), making it the correct answer. Options A, D, and E do not contain oxygen, while option B is not a recognized chemical formula.

Question 20

Which substance is reduced in this redox equation? HF + Cl₂ → F₂ + HCl

Accepted Answer

In the reaction, Cl₂ is reduced to HCl. Chlorine (Cl₂) gains electrons to form chloride ions (Cl^-), indicating reduction.

Quiz 14: Oxidation and Reduction

Which of the following substances is the oxidizing agent in the chemical reaction ? 2CO + 2NO → 2CO₂ + N₂

Rust formation is accelerated in the presence of salt water because_____.

Which substance is the reducing agent in this redox equation? HF + Cl₂ → F₂ + HCl

Which of these occur(s) during oxidation? I. Gaining electrons II. Losing hydrogen III. Losing oxygen

Which of these occur(s) during reduction? I. Losing electrons II. Gaining hydrogen III. Losing oxygen

Which of these statements about redox reactions is incorrect ?

Which substance is the oxidizing agent in this redox reaction? Br⁻(aq) + MnO₄⁻(aq) → Br₂(l) + Mn²⁺(aq)

Which of these occur(s) during oxidation?

Which of these is a redox process? I. Rusting of iron II. Respiration III. Burning hydrocarbons

Which of the following substances is the oxidizing agent in the chemical reaction ? PbCl₄ + SnCl₂ → PbCl₂ + SnCl₄

Redox reactions involve the transfer of _____.

Which of these is not an application of oxidizing agents?

Which of these occurs(s) during reduction?

Which substance is oxidized in this redox reaction? Br⁻(aq) + MnO₄⁻(aq) → Br₂(l) + Mn²⁺(aq)

Which of these is not an oxidation-reduction reaction?

Which of these pairs is correctly matched?

During oxidation-reduction reactions, the substance that loses electrons is _and the substance that gains electrons is _.

Which of these statements about redox reactions is incorrect ?

Which of these substances is the most common oxidizing agent?

Which substance is reduced in this redox equation? HF + Cl₂ → F₂ + HCl

Quiz 14: Oxidation and Reduction

Which of the following substances is the oxidizing agent in the chemical reaction ? 2CO + 2NO → 2CO2 + N2

Rust formation is accelerated in the presence of salt water because_____.

Which substance is the reducing agent in this redox equation? HF + Cl2 → F2 + HCl

Which of these occur(s) during oxidation? I. Gaining electrons II. Losing hydrogen III. Losing oxygen

Which of these occur(s) during reduction? I. Losing electrons II. Gaining hydrogen III. Losing oxygen

Which of these statements about redox reactions is incorrect ?

Which substance is the oxidizing agent in this redox reaction? Br − (aq) + MnO4 − (aq) → Br2(l) + Mn2+(aq)

Which of these occur(s) during oxidation?

Which of these is a redox process? I. Rusting of iron II. Respiration III. Burning hydrocarbons

Which of the following substances is the oxidizing agent in the chemical reaction ? PbCl4 + SnCl2 → PbCl2 + SnCl4

Redox reactions involve the transfer of _____.

Which of these is not an application of oxidizing agents?

Which of these occurs(s) during reduction?

Which substance is oxidized in this redox reaction? Br − (aq) + MnO4 − (aq) → Br2(l) + Mn2+(aq)

Which of these is not an oxidation-reduction reaction?

Which of these pairs is correctly matched?

During oxidation-reduction reactions, the substance that loses electrons is _____and the substance that gains electrons is _____.

Which of these statements about redox reactions is incorrect ?

Which of these substances is the most common oxidizing agent?

Which substance is reduced in this redox equation? HF + Cl2 → F2 + HCl

Which of the following substances is the oxidizing agent in the chemical reaction ? 2CO + 2NO → 2CO₂ + N₂

Which substance is the reducing agent in this redox equation? HF + Cl₂ → F₂ + HCl

Which substance is the oxidizing agent in this redox reaction? Br⁻(aq) + MnO₄⁻(aq) → Br₂(l) + Mn²⁺(aq)

Which of the following substances is the oxidizing agent in the chemical reaction ? PbCl₄ + SnCl₂ → PbCl₂ + SnCl₄

Which substance is oxidized in this redox reaction? Br⁻(aq) + MnO₄⁻(aq) → Br₂(l) + Mn²⁺(aq)

During oxidation-reduction reactions, the substance that loses electrons is _and the substance that gains electrons is _.

Which substance is reduced in this redox equation? HF + Cl₂ → F₂ + HCl