Numford
Oxidation number

P in P₄

P is 0 in white phosphorus.

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.

P0

  1. P₄ is the element on its own, so every P atom is 0.
Rule steps

How to find it

  1. P₄ is the element on its own, so every P atom is 0.
Every atom

All the oxidation numbers in P₄

  • P 04 atoms, element on its own
Questions

P in P₄: quick answers

What is the oxidation number of P in P₄?

P in P₄ (white phosphorus) is 0.

How do you find the oxidation number of P in P₄?

P₄ is the element on its own, so every P atom is 0.

Why is P in P₄ 0?

P₄ is the element on its own, and an element that is not combined with another element always has oxidation number 0.

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