JEE Main · 2021 · 17 Mar 2021 · Shift 1 · p-Block Elements

WhatsApp Email

The reaction of white phosphorous on boiling with alkali in inert atmosphere resulted in the formation of product 'A'. The reaction of 1 mol of 'A' with excess of

AgNO_{3}

in aqueous medium gives ______

mol (s)

of Ag.
(Round off to the nearest integer).

Answer: 4

Solution

White phosphorus reacts with alkali (e.g., NaOH) in an inert atmosphere to form phosphine (

PH_{3}

) as product A:

P_{4} + 3 NaOH + 3 H_{2} O \to PH_{3} + 3 NaH_{2} PO_{2}

When 1 mol of

PH_{3}

reacts with excess

AgNO_{3}

in aqueous medium:

PH_{3} + 3 AgNO_{3} \to Ag_{3} P + 3 HNO_{3}

However, in aqueous medium with excess

AgNO_{3}

, further reaction occurs:

PH_{3} + 4 AgNO_{3} + H_{2} O \to H_{3} PO_{3} + 4 Ag + 4 HNO_{3}

Thus, 1 mol of

PH_{3}

produces 4 mol of Ag.

JEE Main · 2021 · 17 Mar 2021 · Shift 1 · Integer answer

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 →