How To Calculate Oxidation Numbers - Basic Introduction
The Organic Chemistry Tutor・20 minutes read
The text explains how the oxidation state of elements is determined, including rules for single elements, ions, and compounds. It also discusses how electronegativity and charge balancing influence oxidation states in compounds.
Insights
- The oxidation state of elements in pure form is always zero, with exceptions like oxygen, fluorine, and phosphorus.
- Electronegativity plays a crucial role in determining oxidation states, with more electronegative elements often bearing negative charges, such as fluorine consistently having a negative one charge in compounds.
Get key ideas from YouTube videos. It’s free
Recent questions
What is the oxidation state of oxygen in compounds?
-2
How does hydrogen's oxidation state vary based on bonding?
+1 or -1
What is the oxidation state of aluminum in compounds?
+3
How are oxidation states determined in polyatomic ions?
By balancing total charges
What is the average oxidation state of iron in Fe3O4?
8/3 or approximately 2.67
Related videos
Science and Fun Motivation
Redox Reaction Lecture 01 | Oxidation Number Chemistry Class for 11th Class | Science and Fun
Lakshya JEE
D & F Block FULL CHAPTER | Class 12th Inorganic Chemistry | Lakshya JEE
Competition Wallah
d & f BLOCK in 1 Shot: All Concepts, Tricks & PYQs | NEET Crash Course | Ummeed
State Board Wale Bhaiya
Redox Reaction Chapter 6 Class 11th Maharashtra State Board One Shot ( Best Video Ever on YouTube )
JEE Nexus by Unacademy
Redox Reactions Class 11 | JEE Main & Advanced
Summary
00:00
Oxidation States in Elements and Compounds
- The oxidation state of any pure element is always zero, including oxygen, fluorine, and phosphorus.
- For ions, the oxidation state is equal to the charge of the ion, such as zinc 2+ having a positive 2 charge.
- Diatomic ions like mercury 2+ have individual oxidation states of one each.
- In compounds, fluorine always has a negative one oxidation state, while oxygen is typically negative two unless bonded to fluorine, peroxide, or superoxide.
- Hydrogen has a plus one oxidation state when bonded to a non-metal and a negative one when bonded to a metal.
- Compounds like magnesium chloride have oxidation states based on the total charge, with magnesium having a positive two charge.
- Aluminum typically has a positive three charge in compounds, while fluorine is always negative one.
- Vanadium oxide showcases how oxygen has a negative two charge, leading to vanadium having a positive five charge.
- Polyatomic ions like sulfate and phosphate have oxidation states determined by the total charge, with sulfur in sulfate having a positive six charge.
- Electronegativity influences oxidation states, with more electronegative elements bearing negative charges, like fluorine in compounds having a negative one charge.
20:20
Oxidation States in Chemical Compounds Explained
- Oxygen typically has an oxidation state of -2, while carbon is often +4 in certain compounds.
- Elements can have average oxidation states that are not whole numbers, as seen in examples like C3H8 and Fe3O4.
- Iron in Fe3O4 has an average oxidation state of 8/3, which is approximately 2.67, due to the presence of both Fe2+ and Fe3+ ions.
- In polyatomic ions like HSO3-, sulfur has an oxidation state of +4, calculated by balancing the charges of hydrogen and oxygen.
- When analyzing compounds like K2CrO4, the oxidation state of each element can be determined by balancing the charges to achieve a net charge of zero; in this case, chromium has an oxidation state of +6.
