Chapter 21

The correct statement with respect to dinitrogen is: [Main Sep. 06, 2020 (I)] (a) \(\mathrm{N}_{2}\) is paramagnetic in nature. (b) it can combine with dioxygen at \(25^{\circ} \mathrm{C}\). (c) liquid dinitrogen is not used in cryosurgery. (d) it can be used as an inert diluent for reactive chemicals.

Reaction of an inorganic sulphite \(X\) with dilute \(\mathrm{H}_{2} \mathrm{SO}_{4}\) generates compound Y. Reaction of \(\mathrm{Y}\) with NaOH gives \(\mathrm{X}\). Further, the reaction of \(X\) with \(Y\) and water affords compound \(Z . Y\) and \(Z\), respectively, are: [Main Sep. 06, 2020 (II)] (a) \(\mathrm{SO}_{2}\) and \(\mathrm{Na}_{2} \mathrm{SO}_{3}\) (b) \(\mathrm{SO}_{3}\) and \(\mathrm{NaHSO}_{3}\) (c) \(\mathrm{SO}_{2}\) and \(\mathrm{NaHSO}_{3}\) (d) \(\mathrm{S}\) and \(\mathrm{Na}_{2} \mathrm{SO}_{2}\)

Arrange the following bonds according to their average bond energies in descending order: \(\mathrm{C}-\mathrm{Cl}, \mathrm{C}-\mathrm{Br}, \mathrm{C}-\mathrm{F}, \mathrm{C}-\mathrm{I}\) [Main Jan. 08, 2020 (II)] (a) \(\mathrm{C}-\mathrm{F}>\mathrm{C}-\mathrm{Cl}>\mathrm{C}-\mathrm{Br}>\mathrm{C}-\mathrm{I}\) (b) \(\mathrm{C}-\mathrm{Br}>\mathrm{C}-\mathrm{I}>\mathrm{C}-\mathrm{C} 1>\mathrm{C}-\mathrm{F}\) (c) \(\mathrm{C}-\mathrm{I}>\mathrm{C}-\mathrm{Br}>\mathrm{C}-\mathrm{Cl}>\mathrm{C}-\mathrm{F}\) (d) \(\mathrm{C}-\mathrm{Cl}>\mathrm{C}-\mathrm{Br}>\mathrm{C}-\mathrm{I}>\mathrm{C}-\mathrm{F}\)

If the boiling point of \(\mathrm{H}_{2} \mathrm{O}\) is \(373 \mathrm{~K}\), the boiling point of \(\mathrm{H}_{2} \mathrm{~S}\) will be : [Main Sep. \(\mathbf{0 3}, \mathbf{2 0 2 0}\) (I)] (a) less than \(300 \mathrm{~K}\) (b) equal to \(373 \mathrm{~K}\) (c) more than \(373 \mathrm{~K}\) (d) greater than \(300 \mathrm{~K}\) but less than \(373 \mathrm{~K}\)

In the following reactions, products (A) and (B), respectively, are. [Main Jan. 07, 2020 (II)] \(\mathrm{NaOH}+\mathrm{Cl}_{2} \rightarrow(\mathrm{A})+\) side products (hot and conc.) \(\mathrm{Ca}(\mathrm{OH})_{2}+\mathrm{Cl}_{2} \rightarrow(\mathrm{B})+\) side products (dry) (a) \(\mathrm{NaClO}_{3}\), and \(\mathrm{Ca}(\mathrm{OCl})_{2}\) (b) \(\mathrm{NaClO}_{3}\) and \(\mathrm{Ca}\left(\mathrm{ClO}_{3}\right)_{2}\) (c) \(\mathrm{NaOCl}\) and \(\mathrm{Ca}(\mathrm{OCl})_{2}\) (d) \(\mathrm{NaOCl}\) and \(\mathrm{Ca}\left(\mathrm{ClO}_{3}\right)_{2}\)

The noble gas that does NOT occur in the atmosphere is : [Main April 10, 2019 (II)](a) \(\mathrm{He}\) (b) \(\mathrm{Kr}\) (c) \(\mathrm{Ne}\) (d) \(\mathrm{Ra}\)

Reaction of ammonia with excess \(\mathrm{Cl}_{2}\) gives: [Main Sep. 05, 2020 (II)] (a) \(\mathrm{NH}_{4} \mathrm{Cl}\) and \(\mathrm{N}_{2}\) (b) \(\mathrm{NH}_{4} \mathrm{Cl}\) and \(\mathrm{HCl}\) (c) \(\mathrm{NCl}_{3}\) and \(\mathrm{NH}_{4} \mathrm{Cl}\) (d) \(\mathrm{NCl}_{3}\) and \(\mathrm{HCl}\)

A colorless aqueous solution contains nitrates of two metals, \(\mathbf{X}\) and \(\mathbf{Y}\). When it was added to an aqueous solution of \(\mathrm{NaCl}\), a white precipitate was formed. This precipitate was found to be partly soluble in hot water to give a residue \(\mathbf{P}\) and a solution \(\mathbf{Q}\). The residue \(\mathbf{P}\) was soluble in aq. \(\mathrm{NH}_{3}\) and also in excess sodium thiosulfate. The hot solution \(\mathbf{Q}\) gave a yellow precipitate with KI. The metals \(\mathbf{X}\) and \(\mathbf{Y}\), respectively, are [Adv. 2020](a) \(\mathrm{Ag}\) and \(\mathrm{Pb}\) (b) \(\mathrm{Ag}\) and \(\mathrm{Cd}\) (c) \(\mathrm{Cd}\) and \(\mathrm{Pb}\) (d) \(\mathrm{Cd}\) and \(\mathrm{Zn}\)

The type of hybridisation and number of lone pair(s) of electrons of \(\mathrm{Xe}\) in \(\mathrm{XeOF}_{4}\), respectively, are: [Main Jan. 10, 2019 (I)](a) \(s p^{3} d^{2}\) and 1 (b) \(s p^{3} d\) and 2 (c) \(s p^{3} d^{2}\) and 2 (d) \(s p^{3} d\) and 1

On heating, lead (II) nitrate gives a brown gas (A). The gas (A) on cooling changes to a colourless solid/liquid (B). (B) on heating withNO changes to a blue solid (C). The oxidation number of nitrogen in solid (C) is : [Main Sep. 04, 2020 (I)] (a) \(+5\) (b) \(+2\) (c) \(+3\) \((\mathrm{d})+4\)

The oxoacid of sulphur that does not contain bond between Sulphur atoms is : [Main April 10, 2019 (I)] (a) \(\mathrm{H}_{2} \mathrm{~S}_{4} \mathrm{O}_{6}\) (b) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) (c) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{7}\) (d) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{4}\)

HF has highest boiling point among hydrogen halides, because it has: [Main April 9, 2019 (II)] (a) strongest van der Waals' interactions (b) lowest ionic character (c) strongest hydrogen bonding (d) lowest dissociation enthalpy

In \(\mathrm{XeO}_{3} \mathrm{~F}_{2}\), the number of bond pair(s), \(\pi\)-bond(s) and lone pair(s) on Xe atom respectively are: [Main Online April 15, \(\mathbf{2 0 1 8}\) (II)](a) \(5,3,0\) (b) \(5,2,0\) (c) \(4,2,2\) (d) \(4,4,0\)

Aqua regia is used for dissolving noble metals (Au, Pt, etc.). The gas evolved in this process is: [Main Sep. 03, 2020 (I)] (a) NO (b) \(\mathrm{N}_{2} \mathrm{O}_{5}\) (c) \(\mathrm{N}_{2}\) (d) \(\mathrm{N}_{2} \mathrm{O}_{3}\)

In \(\mathrm{KO}_{2}\), the nature of oxygen species and the oxidation state of oxygen atom are, respectively: [Main Online April 15, 2018 (II)](a) Superoxide and \(-1\) (b) Superoxide and \(-1 / 2\)(c) Peroxide and \(-1 / 2\) (d) Oxide and \(-2\)

Chlorine on reaction with hot and concentrated sodium hydroxide gives: [Main Jan. 12, 2019 (II)] (a) \(\mathrm{Cl}\) and \(\mathrm{ClO}_{3}^{-}\) (b) \(\mathrm{Cl}^{-}\)and \(\mathrm{ClO}^{-}\) (c) \(\mathrm{ClO}_{3}^{-}\)and \(\mathrm{ClO}_{2}^{-}\) (d) \(\mathrm{Cl}^{-}\)and \(\mathrm{ClO}_{2}^{-}\)

Which intermolecular force is most responsible in allowing xenon gas to liquefy? [Main Online April 9, 2016](a) Instantaneous dipole-induced dipole (b) Ion-dipole (c) Ionic (d) Dipole \(-\) dipole

In a molecule of pyrophosphoric acid, the number of \(\mathrm{P}-\mathrm{OH}, \mathrm{P}=\mathrm{O}\) and \(\mathrm{P}-\mathrm{O}-\mathrm{P}\) bonds/ moiety(ies) respectively are : [Main Sep. 03, 2020 (I)] (a) 2,4 and 1 (b) 3,3 and 3 (c) 4,2 and 0 (d) 4,2 and 1

The products obtained when chlorine gas reacts with cold and dilute aqueous \(\mathrm{NaOH}\) are : [Main 2017] (a) \(\mathrm{ClO}\) and \(\mathrm{ClO}_{3}\) (b) \(\mathrm{ClO}_{2}\) and \(\mathrm{ClO}_{3}\) (c) \(\mathrm{Cl}^{-}\)and \(\mathrm{ClO}^{-}\) (d) \(\mathrm{Cl}^{-}\)and \(\mathrm{ClO}_{2}\)

Which one has the highest boiling point? [Main 2015] (a) \(\mathrm{Kr}\)(b) Xe (c) He (d) \(\mathrm{Ne}\)

On heating compound (A) gives a gas (B) which is a constituent of air. This gas when treated with \(\mathrm{H}_{2}\) in the presence of a catalyst gives another gas (C) which is basic in nature. (A) should not be : [Main Sep. 02, 2020 (I)] (a) \(\mathrm{NaN}_{3}\) (b) \(\mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2}\) (c) \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) (d) \(\mathrm{NH}_{4} \mathrm{NO}_{2}\)

iline \(\mathrm{A}_{1}\) (a) The S-S-S bond angles in the \(\mathrm{S}_{8}\) and \(\mathrm{S}_{6}\) rings are the same. (b) Rhombic and monoclinic sulphur have \(\mathrm{S}_{8}\) molecules. (c) \(\mathrm{S}_{2}\) is paramagnetic like oxygen (d) \(\mathrm{S}_{8}\) ring has a crown shape.

Aqueous solution of which salt will not contain ions with the electronic configuration \(1 \mathrm{~s}^{2} 2 \mathrm{~s}^{2} 2 \mathrm{p}^{6} 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} ?\) [Main Online April 10, 2016] (a) \(\mathrm{NaF}\) (b) \(\mathrm{KBr}\) (c) \(\mathrm{NaCl}\) (d) \(\mathrm{CaI}_{2}\)

The geometry of \(\mathrm{XeOF}_{4}\) by VSEPR theory is : [Main Online April 10, 2015](a) pentagonal planar (b) octahedral (c) square pyramidal (d) trigonal bipyramidal

White phosphorus on reaction with concentrated \(\mathrm{NaOH}\) solution in an inert atmosphere of \(\mathrm{CO}_{2}\) gives phosphine and compound \((X) .(X)\) on acidification with \(\mathrm{HCl}\) gives compound \((Y)\). The basicity of compound (Y) is: [Main Jan. 08, 2020 (II)] (a) 2 (b) 1 (c) 4 (d) 3

In the following reaction sequence in aqueous solution, the species \(X\), \(Y\) and \(Z\), respectively, are [Adv. 2016] \(\stackrel{\text { with time }}{\longrightarrow} \begin{gathered}Z \\ \text { black precipitate }\end{gathered}\)(a) \(\left[\mathrm{Ag}\left(\mathrm{S}_{2} \mathrm{O}_{3}\right)_{2}\right]^{3}, \mathrm{Ag}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}, \mathrm{Ag}_{2} \mathrm{~S}\) (b) \(\left[\mathrm{Ag}\left(\mathrm{S}_{2} \mathrm{O}_{3}\right)_{3}\right]^{5-}, \mathrm{Ag}_{2} \mathrm{SO}_{3}, \mathrm{Ag}_{2} \mathrm{~S}\) (c) \(\left[\mathrm{Ag}\left(\mathrm{SO}_{3}\right)_{2}\right]^{3-}, \mathrm{Ag}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}, \mathrm{Ag}\) (d) \(\left[\mathrm{Ag}\left(\mathrm{SO}_{3}\right)_{3}\right]^{3}, \mathrm{Ag}_{2} \mathrm{SO}_{4}, \mathrm{Ag}\)

(b) \(\mathrm{IC} 1\) (c) \(\mathrm{Cl}_{2}\) (d) \(\mathrm{Br}_{2}\)Which among the following is the most reactive? [Main 2015] (a) \(\mathrm{I}_{2}\)

Which of the following xenon-oxo compounds may not be obtained by hydrolysis of xenon fluorides? [Main Online April 12, 2014](a) \(\mathrm{XeO}_{2} \mathrm{~F}_{2}\) (b) \(\mathrm{XeOF}_{4}\) (c) \(\mathrm{XeO}_{3}\) (d) \(\mathrm{XeO}_{A}\)

The number of pentagons in \(\mathrm{C}_{60}\) and trigons (triangles) in white phosphorous, respectively, are : [Main April \(\mathbf{1 0}, \mathbf{2 0 1 9}\) (II)] (a) 20 and 3 (b) 12 and 4 (c) 12 and 3 (d) 20 and 4

Aqueous solution of \(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) on reaction with \(\mathrm{Cl}_{2}\) gives \(-\)(a) \(\mathrm{Na}_{2} \mathrm{~S}_{4} \mathrm{O}_{6}\) (b) \(\mathrm{NaHSO}_{4}\) (c) \(\mathrm{NaCl}\) (d) \(\mathrm{NaOH}\)

Chlorine water on standing loses its colour and forms : [Main Online April 11, 2015] (a) HCl only (b) \(\mathrm{HCl}\) and \(\mathrm{HClO}_{2}\) (c) \(\mathrm{HCl}\) and \(\mathrm{HOCl}\) (d) \(\mathrm{HOCl}\) and \(\mathrm{HOCl}_{2}\)

The correct order of the oxidation states of nitrogen in \(\mathrm{NO}, \mathrm{N}_{2} \mathrm{O}, \mathrm{NO}_{2}\) and \(\mathrm{N}_{2} \mathrm{O}_{3}\) is: [Main April 9, 2019 (I)] (a) \(\mathrm{NO}_{2}<\mathrm{NO}<\mathrm{N}_{2} \mathrm{O}_{3}<\mathrm{N}_{2} \mathrm{O}\) (b) \(\mathrm{NO}_{2}<\mathrm{N}_{2} \mathrm{O}_{3}<\mathrm{NO}<\mathrm{N}_{2} \mathrm{O}\) (c) \(\mathrm{N}_{2} \mathrm{O}<\mathrm{N}_{2} \mathrm{O}_{3}<\mathrm{NO}<\mathrm{NO}_{2}\) (d) \(\mathrm{N}_{2} \mathrm{O}<\mathrm{NO}<\mathrm{N}_{2} \mathrm{O}_{3}<\mathrm{NO}_{2}\)

\text { Which of the following is not oxidized by } \mathrm{O}_{3} \text { ? }(a) KI (b) \(\mathrm{FeSO}_{4}\) (c) \(\mathrm{KMnO}_{4}\) (d) \(\mathrm{K}_{2} \mathrm{MnO}_{4}\)

Shapes of certain interhalogen compounds are stated below. Which one of them is not correctly stated? [Main Online April 11, 2014] (a) \(\mathrm{IF}_{7}:\) pentagonal bipyramid (b) \(\mathrm{BrF}_{5}\) : trigonal bipyramid (c) \(\mathrm{BrF}_{3}\) : planar T-shaped (d) ICI. ' planar dimeric

The shape of \(\mathrm{XeO}_{2} \mathrm{~F}_{2}\) molecule is(a) trigonal bipyramidal (b) square planar (c) tetrahedral (d) see-saw

The pair that contains two P-H bonds in each of the oxoacids is: [Main Jan. 10, 2019 (II)] (a) \(\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{5}\) and \(\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{6}\) (b) \(\mathrm{H}_{3} \mathrm{PO}_{2}\) and \(\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{5}\) (c) \(\mathrm{H}_{3} \mathrm{PO}_{3}\) and \(\mathrm{H}_{3} \mathrm{PO}_{2}\) (d) \(\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{5}\) and \(\mathrm{H}_{3} \mathrm{PO}_{3}\)

The acid having \(\mathrm{O}-\mathrm{O}\) bond is [2004S] (a) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) (b) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{6}\) (c) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{8}\) Page \(543 / 1,773-\mathbb{Q}\) ? (d) \(\mathrm{H}_{2} \mathrm{~S}_{4} \mathrm{O}_{6}\)

Electron gain enthalpy with negative sign of fluorine is less than that of chlorine due to : [Main Online April 9, 2013] (a) High ionization enthalpy of fluorine (b) Smaller size of chlorine atom (c) Smaller size of fluorine atom (d) Bigger size of \(2 p\) orbital of fluorine

Total number of lone pair of electrons with central atom in \(\mathrm{XeOF}_{4}\) is [2004S](a) 0 (b) 1 (c) 2 (d) 3

Good reducing nature of \(\mathrm{H}_{3} \mathrm{PO}_{2}\) is attributed to the presence of: [Main Jan. 9, 2019 (II)] (a) Two \(\mathrm{P}-\mathrm{OH}\) bonds (b) One \(\mathrm{P}-\mathrm{H}\) bond (c) Two \(\mathrm{P}-\mathrm{H}\) bonds (d) One P - OH bond

The number of \(S-S\) bonds in sulphur trioxide trimer \(\left(\mathrm{S}_{3} \mathrm{O}_{9}\right)\) is [2001S] (a) three (b) two (c) one (d) zero

Which one of the following species is not a pseudohalide? [1997 - 1 Mark] (a) \(\mathrm{CNO}^{-}\) (b) \(\mathrm{RCOO}^{-}\) (c) \(\mathrm{OCN}\) (d) \(\mathrm{NNN}\)

At \(143 \mathrm{~K}\), the reaction of \(\mathrm{XeF}_{4}\) with \(\mathrm{O}_{2} \mathrm{~F}_{2}\), produces a xenon compound \(Y\). The total number of lone pair(s) of electron present on the whole molecule of \(Y\) is [Adv. 2019]

The compound that does not produce nitrogen gas by the thermal decomposition is: [Main 2018] (a) \(\mathrm{Ba}\left(\mathrm{N}_{3}\right)_{2}\) (b) \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) (c) \(\mathrm{NH}_{4} \mathrm{NO}_{2}\) (d) \(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{SO}_{4}\)

Sodium thiosulphate is prepared by [1996-1 Mark] (a) reducing \(\mathrm{Na}_{2} \mathrm{SO}_{4}\) solution with \(\mathrm{H}_{2} \mathrm{~S}\) (b) boiling \(\mathrm{Na}_{2} \mathrm{SO}_{3}\) solution with \(\mathrm{S}\) in alkaline medium (c) neutralising \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) solution with \(\mathrm{NaOH}\) (d) boiling \(\mathrm{Na}_{2} \mathrm{SO}_{3}\) solution with \(\mathrm{S}\) in acidic medium

The unbalanced chemical reactions given in List I show missing reagent or condition (?) which are provided in List II. Match List I with List II and select the correct answer using the code given below the lists [Adv. 2013-II] List I List II P. \(\mathrm{PbO}_{2}+\mathrm{H}_{2} \mathrm{SO}_{4} \stackrel{?}{\longrightarrow}\) 1\. \(\mathrm{NO}\) \(\mathrm{PbSO}_{4}+\mathrm{O}_{2}+\) other product Q. \(\quad \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}+\mathrm{H}_{2} \mathrm{O} \stackrel{?}{\longrightarrow}\) 2\. \(\quad I_{2}\) \(\mathrm{NaHSO}_{4}+\) other product R. \(\quad \mathrm{N}_{2} \mathrm{H}_{4} \stackrel{?}{\longrightarrow} \mathrm{N}_{2}+\) other product 3\. Warm S. \(\quad \mathrm{XeF}_{2} \stackrel{?}{\longrightarrow} \mathrm{Xe}+\) other product 4\. \(\mathrm{Cl}_{2}\)Codes : \(\mathrm{P} \mathrm{Q} \mathrm{R} \mathrm{S}\) (a) \(\quad 4231\) (b) 3214 (c) 1423 (d) \(\quad 34421\)

The number of P \(-\mathrm{O}\) bonds in \(\mathrm{P}_{4} \mathrm{O}_{6}\) is: [Main Online April 15, \(\mathbf{2 0 1 8}\) (II)] (a) 9 (b) 6 (c) 12 (d) 18

Hydrolysis of one mole of peroxodisulphuric acid produces (a) two moles of sulphuric acid [1996 - 1 Mark] (b) two moles of peroxomonosulphuric acid (c) one mole of sulphuric acid and one mole of peroxomonosulphuric acid (d) one mole of sulphuric acid, one mole of peroxomonosulphuric acid and one mole of hydrogen peroxide.

Which of the following statements is correct for \(\mathrm{CsBr}_{3}\) ? (a) It is a covalent compound. [1996-1 Mark] (b) It contains \(\mathrm{Cs}^{3+}\) and \(\mathrm{Br}^{-}\)ions. (c) It contains \(\mathrm{Cs}^{+}\)and Br_ions (d) It contains \(\mathrm{Cs}^{+}\), and \(\mathrm{Br}^{-}\)and lattice \(\mathrm{Br}_{2}\) molecule

All the compounds listed in Column I react with water. Match the result of the respective reactions with the appropriate options listed in Column II.Column-I Column-II (A) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{SiCl}_{2}\) (p) Hydrogen halide formation (B) \(\mathrm{XeF}_{4}\) (q) Redox reaction (C) \(\mathrm{Cl}_{2}\) (r) Reacts with glass (D) \(\mathrm{VCl}_{5}\) (s) Polymerization (t) \(\mathrm{O}_{2}\) formation