Question

Which of the Phosphorus oxoacid can create silver mirror from $AgNO _3$ solution?

• A. $H _4 P _2 O _7$
• B. $\left( HPO _3\right)_n$
• C. $H _4 P _2 O _6$
• D. $H _4 P _2 O _5$

Answer 1

Answer: (D)

$H _4 P _2 O _5$

Answer 2

Oxyacid having P-H bond can reduce $AgNO_3$ to $Ag$.

So, the correct option is (D): $H_4​P_2​O_5$​.