Problem 16 - Chemistry The Central Science In Si Units

Question

Indicate whether each of the following statements is true or false: (a) If something is reduced, it is formally losing electrons. (b) A reducing agent gets oxidized as it reacts. (c) An oxidizing agent is needed to convert \(\mathrm{CO}\) into \(\mathrm{CO}_{2}\).

Step-by-Step Solution

Answer

(a) False, (b) True, (c) True.

Step 1: Analyze statement (a)

The statement "If something is reduced, it is formally losing electrons" suggests that reduction involves the loss of electrons. However, in a redox reaction, reduction actually means the gain of electrons. Therefore, statement (a) is false.

Step 2: Analyze statement (b)

The statement "A reducing agent gets oxidized as it reacts" explains the role of a reducing agent in a redox reaction. A reducing agent donates electrons and is oxidized in the process. Therefore, statement (b) is true.

Step 3: Analyze statement (c)

The statement "An oxidizing agent is needed to convert \(\mathrm{CO}\) into \(\mathrm{CO}_2\)" involves the conversion of carbon monoxide to carbon dioxide. In this conversion, \(\mathrm{CO}\) gains oxygen (or equivalently electrons are transferred from \(\mathrm{CO}\) to oxygen), requiring an oxidizing agent to facilitate the reaction. Therefore, statement (c) is true.

Key Concepts

Reduction

Reduction is a key concept in redox reactions, standing for the process where a substance gains electrons. It's crucial to not confuse this with the idea of losing electrons.
When a molecule, atom, or ion is reduced, it is undergoing a decrease in oxidation state due to the gain of electrons.
This can often be remembered through the mnemonic "OIL RIG," which stands for "Oxidation Is Loss, Reduction Is Gain" of electrons.

• Reducing the oxidation number is equivalent to gaining negative charge (electrons).
• It's important to recognize the substance that is reduced in a chemical reaction to understand the flow of electrons.

Understanding reduction helps in balancing redox equations and in predicting the course of chemical reactions, which is fundamental in chemistry.

Oxidation

Oxidation refers to the process where a substance loses electrons. It's the opposite of reduction and is essential for a redox (reduction-oxidation) reaction to take place.
This involves an increase in the oxidation state of a molecule, atom, or ion caused by the loss of electrons.
The mnemonic "OIL RIG" is useful here as well, as it helps remember that "Oxidation Is Loss" of electrons.

• Oxidation often involves gaining oxygen or losing hydrogen.
• The substance that undergoes oxidation is responsible for providing electrons for reduction to occur.

Understanding oxidation is vital in various chemical processes, from cellular respiration to rusting of metals.

Reducing Agent

A reducing agent, also known as a reductant, is a substance that causes reduction by donating electrons to another species.
In the process, the reducing agent itself becomes oxidized because it loses electrons.
This concept is especially important in analyzing chemical reactions where electron transfer is involved.

• Reducing agents are typically metals or hydrides.
• The stronger the reducing agent, the more readily it donates electrons.

Understanding the role of a reducing agent allows chemists to manipulate chemical reactions, especially in synthesis and industrial processes.

Oxidizing Agent

An oxidizing agent, also known as an oxidant, is a substance that causes oxidation by accepting electrons from another species.
As it accepts electrons, it undergoes reduction.
Oxidizing agents are crucial for many chemical transformations, such as converting carbon monoxide to carbon dioxide in statement (c) from the exercise.

• Oxidizing agents often contain elements that are highly electronegative, like oxygen or halogens.
• The stronger the oxidizing agent, the more effectively it can gain electrons during a reaction.

Exploiting the characteristics of oxidizing agents can be useful in areas ranging from energy production to disinfection and synthesis.