Question

In which species does phosphorous have the highest oxidation number?

a. HPO₂
b. Li₃PO₃
c. H₃PO₄
d. P₄ (elemental phosphorous)

Answer 1

In the species H₃PO₄, phosphorus has the highest oxidation number, which is +5.

Step-by-step explanation:

The question is asking to determine which species has phosphorus with the highest oxidation number. Phosphorus commonly exhibits oxidation states such as +3 and +5 when bonded to more electronegative elements like oxygen. To find the highest oxidation state of phosphorus among the given options:

1. HPO₂: Phosphorus has an oxidation state of +4 here.
2. Li₃PO₃: Phosphorus has an oxidation state of +3 here.
3. H₃PO₄: Phosphorus has an oxidation state of +5 here, which is the highest among all given options.
4. P₄ (elemental phosphorous): Phosphorus is in its elemental state, so its oxidation number is 0.

Therefore, in H₃PO₄, phosphorus has the highest oxidation number of +5.