Which of the Phosphorus oxoacid can create silver mirror from $\mathrm{AgNO}_{3}$ solution ?

(B) $\mathrm{H}_{4}\mathrm{P}_{2}\mathrm{O}_{5}$

(A) $(\mathrm{HPO}_{3})_{\mathrm{n}}$

(C) $\mathrm{H}_{4}\mathrm{P}_{2}\mathrm{O}_{6}$

(D) $\mathrm{H}_{4}\mathrm{P}_{2}\mathrm{O}_{7}$

JEE Main · 2023 · 24 Jan 2023 · Shift 1 · p-Block Elements

Which of the Phosphorus oxoacid can create silver mirror from

AgNO_{3}

solution ?

(A) $(HPO_{3})_{n}$
(B) $H_{4} P_{2} O_{5}$ ✓ Correct
(C) $H_{4} P_{2} O_{6}$
(D) $H_{4} P_{2} O_{7}$

Answer: (B)

Solution

A phosphorus oxoacid can reduce silver ion to the metallic silver of a mirror only when it carries a phosphorus–hydrogen bond. Metaphosphoric acid, hypophosphoric acid and pyrophosphoric acid hold all their hydrogens on oxygen and cannot reduce silver. Diphosphorous (pyrophosphorous) acid,

H_{4} P_{2} O_{5}

, has two

P - H

bonds and acts as a reducing agent, depositing a silver mirror from silver nitrate.

JEE Main · 2023 · 24 Jan 2023 · Shift 1 · Single correct option

Practise more: all JEE Main PYQs on p-Block Elements →

More JEE Main questions on p-Block Elements

Given below are two statements:

Statement I: The number of pairs among [ $SiO_{2}, CO_{2}$ ], $[SnO, SnO_{2}], [PbO, PbO_{2}]$ and $[GeO, GeO_{2}]$ , which contain oxides t …
JEE Main 2026View solution →
A 'p'-block element (E) and hydrogen form a binary cation $(EH_{x})^{+}$ , while $EH_{3}$ on treatment with $K_{2} HgI_{4}$ in alkaline medium gives a precipitate of basic mercury(II)amido-iodine. Given below are first …
JEE Main 2026View solution →
Given below are two statements :

Statement I: The halogen that makes longest bond with hydrogen in HX, has the smallest covalent radius in its group.

Statement II : A group 15 element's hydride $EH_{3}$ has the lowest boiling point among corresponding hydrides of oth …
JEE Main 2026View solution →
Two p-block elements X and Y form fluroides of the type $EF_{3}$ . The fluoride compound $XF_{3}$ is a Lewis acid and $YF_{3}$ is a Lewis base. The hybridization of the central atoms of $XF_{3}$ and $YF_{3}$ respectively are
JEE Main 2026View solution →
Given below are two statements:

Statement I: The correct order in terms of bond dissociation enthalpy is $Cl_{2} > Br_{2} > F_{2} > I_{2}$
Statement II: The correct trend in the covalent character of the metal halides is …
JEE Main 2026View solution →
Given below are two statements :

Statement-I : Element ' X ' and $^{'} Y$ ' are the most and least electronegative elements, respectively among $N, As, Sb$ and P . The nature of the oxides $X_{2} O_{3}$ and …
JEE Main 2026View solution →