JEE Advanced2013Chemistryp Block Elements (Group 15, 16, 17 & 18)Actual
Paragraph: The reactions of Cl ₂ gas with cold-dilute and hot-concentrated NaOH in water give sodium salts of two (different) oxoacids of chlorine, P and Q , respectively. The Cl ₂ gas reacts with SO ₂ gas, in presence of charcoal, to give a product R . R reacts with white phosphorus to give a compound S . On hydrolysis, S gives an oxoacid of phosphorus, T . Question: P and Q , respectively, are the sodium salts of
Options
- AHypochlorous and chloric acids
- BHypochlorus and chlorous acids
- CChloric and perchloric acids
- DChloric and hypochlorous acids
Correct answer
A. Hypochlorous and chloric acids
Step-by-step solution
Cl 2 + cold dil. NaOH → NaOCl + NaCl Cl 2 + hot conc.  NaOH → NaClO 3 + NaCl NaOCl is salt of hypochlorous acid =   P . NaOCl 3 is salt of chloric acid =   Q . Cl 2 + SO 2 ⟶ Charcoal SO 2 Cl 2 R SO 2 Cl 2 + P 4 ⟶ PCl 5 S + SO 2 PCl 5 + H 2 O ⟶ H 3 PO 4 T + HCl