Hello Harika,

The oxidation state or oxidation number basically means the total number of electrons that an atom either gains or loses to form a chemical bond with another atom.

Phosphorus has more than one oxidation number. These are -3,+3 and +5.

Hi,

Your questions is not so clear, aa far as I can understand you want to ask the oxidation number of phosphorous in phosphoric acid

Answer is + 5

Phosphorous occur in its higher oxidation state .

Oxygen has an oxidation state of -2 .

Hope u got ur answer