Problem 15 - Chemistry An Atoms First Approach

Question

Define oxidation and reduction in terms of both change in oxidation number and electron loss or gain.

Step-by-Step Solution

Answer

Oxidation is a chemical process where a substance loses electrons and experiences an increase in its oxidation number, while reduction is a chemical process where a substance gains electrons and experiences a decrease in its oxidation number. For example, when a carbon atom goes from +2 to +4 oxidation state, it has been oxidized; and when an oxygen atom goes from -1 to -2 oxidation state, it has been reduced. Additionally, oxidation involves electron loss (e.g., sodium atom losing an electron to become Na+), and reduction involves electron gain (e.g., chlorine atom gaining an electron to become Cl-).

Step 1: Definition of Oxidation

Oxidation is a chemical process in which a substance loses electrons, leading to an increase in its oxidation number.

Step 2: Definition of Reduction

Reduction is a chemical process in which a substance gains electrons, leading to a decrease in its oxidation number.

Step 3: Oxidation in terms of oxidation number

Oxidation occurs when there is an increase in the oxidation number of an atom, ion, or molecule. For example, when a carbon atom goes from an oxidation state of +2 to +4, it has been oxidized.

Step 4: Reduction in terms of oxidation number

Reduction occurs when there is a decrease in the oxidation number of an atom, ion, or molecule. For example, when an oxygen atom goes from an oxidation state of -1 to -2, it has been reduced.

Step 5: Oxidation in terms of electron loss

In oxidation, a substance loses electrons during the chemical process. For example, when a sodium atom loses an electron to become a sodium ion (Na+), it has undergone oxidation.

Step 6: Reduction in terms of electron gain

In reduction, a substance gains electrons during the chemical process. For example, when a chlorine atom gains an electron to become a chloride ion (Cl-), it has undergone reduction.