KCET2023Chemistryp Block Elements (Group 15, 16, 17 & 18)
Which one of the following oxoacids of phosphorus can reduce AgNO ₃ to metallic silver?
Options
- AH ₃ PO ₂
- BH ₄ P ₂ O ₇
- CH ₄ P ₂ O ₆
- DH ₃ PO ₄
Correct answer
A. H ₃ PO ₂
Step-by-step solution
Hypophosphorus acid ( H ₃ PO ₂ ) is a strong reducing agent which can effectively reduce Ag ⁺ ions to Ag and itself gets oxidise to phosphorus acid [ H ₃ PO ₃ ] as follows aligned 3 AgNO ₃+4 H ₃ PO ₂+ H ₂ O & 3 Ag +4 H ₃ PO ₃ & +3 HNO ₃ aligned