Oxidation State Calculator
Calculate oxidation states of elements in compounds. Determine oxidation numbers using standard rules.
Enter Compound
Common Compounds:
Oxidation State Rules:
- - Free elements have oxidation state 0
- - H is usually +1 (except in hydrides: -1)
- - O is usually -2 (except in peroxides: -1)
- - F is always -1
- - Alkali metals (Na, K) are +1
- - Alkaline earth metals (Ca, Mg) are +2
- - Sum of oxidation states = charge of species
Target Element Oxidation State
Fe: +3
Oxidation States in Fe2O3:
Fe2+3
O3-2
Verification:
Sum of all oxidation states: 0 = 0 (compound charge)
About Oxidation States
Oxidation state (or oxidation number) represents the degree of oxidation of an atom in a chemical compound. It is the hypothetical charge an atom would have if all bonds were completely ionic. Oxidation states are essential for understanding redox reactions, balancing equations, and predicting chemical behavior.