Numford
Oxidation number

Cr in CrO₅

Cr is +6 in chromium peroxide.

Oxidation number

Type a formula or an ion: K2Cr2O7, Cr2O7 2-, MnO4-, NH4+ or K4[Fe(CN)6]. Put a known ion in brackets when two elements are unknown. Pick an element to solve for it.

Cr+6

CrO₅ has two peroxide groups: four O atoms are −1 and one is −2. So Cr is +6, not +10.

  1. CrO₅ has two peroxide groups: four O atoms are −1 and one is −2. So Cr is +6, not +10.
  2. So Cr in CrO₅ is +6.
Rule steps

How to find it

  1. CrO₅ has two peroxide groups: four O atoms are −1 and one is −2. So Cr is +6, not +10.
  2. So Cr in CrO₅ is +6.

CrO₅ has two peroxide groups: four O atoms are −1 and one is −2. So Cr is +6, not +10.

Every atom

All the oxidation numbers in CrO₅

  • Cr +61 atom, structure
  • O −6/55 atoms, structure
Questions

Cr in CrO₅: quick answers

What is the oxidation number of Cr in CrO₅?

Cr in CrO₅ (chromium peroxide) is +6. CrO₅ has two peroxide groups: four O atoms are −1 and one is −2. So Cr is +6, not +10.

How do you find the oxidation number of Cr in CrO₅?

CrO₅ has two peroxide groups: four O atoms are −1 and one is −2. So Cr is +6, not +10. So Cr in CrO₅ is +6.

What are the oxidation numbers of the other atoms in CrO₅?

O −6/5. Together with Cr at +6 they add up to the charge of the compound, 0.

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