Ncert Exercises & Solutions

Identify the correct statements with reference to the given reaction

4P + 3KOH + 3H₂O → 3KH₂PO₂ + PH₃:

1. Phosphorus is undergoing reduction only

2. Phosphorus is undergoing oxidation only

3. Phosphorus is undergoing oxidation as well as reduction

4. Hydrogen is undergoing neither oxidation nor reduction

4P + 3KOH + 3H₂O → 3KH₂PO₂ + PH₃

Oxidation states of P:

Thus, phosphorus undergoes both oxidation and reduction in the same reaction. This is a disproportionation reaction.

Correct answer: 3. P is oxidised as well as reduced.