What Are Unusual Oxidation States of Oxygen?

TL;DR

Oxygen typically has an oxidation state of -2 due to its electronegativity. However, in hydrogen peroxide, its oxidation state is -1 when bonded to another oxygen atom, while in oxygen difluoride, it can reach +2 because fluorine is more electronegative. Thus, oxidation states can vary based on the bonding environment.

Transcript

So we have two different molecules here. This is hydrogen peroxide. We call it peroxide, because it has this oxygen-oxygen bond. And here we have oxygen difluoride, where oxygen is bonded to two different fluorines. And what I want you to do is pause this video, use this periodic table of elements I have here, and this is more than just a typical i... Read More

Key Insights

• ✋ Oxygen usually has an oxidation state of -2 due to its high electronegativity.
• 🫀 In hydrogen peroxide, oxygen has an oxidation state of -1 because it is equally electronegative to the other oxygen atom.
• ✋ Oxygen difluoride shows a dramatic deviation from the typical oxidation state of oxygen, with an oxidation state of +2 due to fluorine's higher electronegativity.
• ❓ The oxidation state of oxygen depends on its bonding partners and their electronegativities.
• ❓ Fluorine is the only element more electronegative than oxygen.
• ⚾ Oxidation states are determined based on hypothetical ionic bonds rather than the actual covalent bonds in molecules.
• ❓ Oxygen's oxidation state can vary depending on the compound and its bonding arrangement.

Questions & Answers

Q: Why is oxygen typically assigned an oxidation state of -2?

Oxygen is highly electronegative and tends to take electrons from other elements, resulting in an oxidation state of -2.

Q: Why does oxygen have an oxidation state of -1 in hydrogen peroxide?

In hydrogen peroxide, oxygen is equally electronegative to the other oxygen atom it is bonded to. If we assume the covalent bond is ionic, the electrons would be given to the oxygen atom, resulting in an oxidation state of -1 for oxygen.

Q: What happens to the oxidation state of oxygen in oxygen difluoride?

Oxygen difluoride is interesting because fluorine is more electronegative than oxygen. In a hypothetical ionic bond, the electrons would be given to fluorine, resulting in an oxidation state of +2 for oxygen.

Q: When does oxygen deviate from its typical oxidation state of -2?

Oxygen deviates from its typical oxidation state when bonded to another oxygen atom or fluorine. In these cases, the oxidation state can be -1 or +2, respectively.

Summary & Key Takeaways

• Oxygen usually has an oxidation state of -2 because it is highly electronegative and tends to take electrons from other elements.

• In hydrogen peroxide, the oxidation state of oxygen is -1 because it is equally electronegative to the other oxygen atom it is bonded to.

• In oxygen difluoride, the oxidation state of oxygen is +2 because fluorine, which is more electronegative, takes the electrons from oxygen.