Numford
Oxidation number

Cl in KClO₃

Cl is +5 in potassium chlorate.

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.

Cl+5

  1. K is an alkali metal: +1 in its compounds.
  2. Oxygen is −2 in most compounds.
  3. The oxidation numbers add up to the charge, 0: (+1) + 3(−2) + x = 0.
  4. x = +5.
Rule steps

How to find it

  1. K is an alkali metal: +1 in its compounds.
  2. Oxygen is −2 in most compounds.
  3. The oxidation numbers add up to the charge, 0: (+1) + 3(−2) + x = 0.
  4. x = +5.
Every atom

All the oxidation numbers in KClO₃

  • K +11 atom, alkali metal
  • O −23 atoms, oxygen
  • Cl +51 atom, sum rule
Questions

Cl in KClO₃: quick answers

What is the oxidation number of Cl in KClO₃?

Cl in KClO₃ (potassium chlorate) is +5.

How do you find the oxidation number of Cl in KClO₃?

K is an alkali metal: +1 in its compounds. Oxygen is −2 in most compounds. The oxidation numbers add up to the charge, 0: (+1) + 3(−2) + x = 0. x = +5.

What are the oxidation numbers of the other atoms in KClO₃?

K +1, O −2. Together with Cl at +5 they add up to the charge of the compound, 0.

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