Chemistry - Complete P-block Question with Solution | TestHub

The element described (white waxy solid with a garlic odor) is white phosphorus (P₄).

Step 1: One mole of the acidic oxide in its highest oxidation state (+5) is P₄O₁₀.

Step 2: Reacting P₄O₁₀ with water yields orthophosphoric acid (H₃PO₄).

Step 3: Subsequent heating and re-hydrolysis with excess water ultimately converts the phosphorus back into H₃PO₄ (oxy acid A).

Conclusion: Since 1 mole of P₄O₁₀ contains 4 moles of phosphorus atoms, it can form a maximum of 4 moles of H₃PO₄.

Correct Option: (C) 4