Chapter 16

Which of the following attacks glass? (a) \(\mathrm{HCl}\) (b) \(\mathrm{HBr}\) (c) \(\mathrm{HI}\) (d) HF

Which species has the maximum number of lone pair of electrons on the central atom? (a) \(\left[\mathrm{I}_{3}\right]\) (b) \(\mathrm{XeF}_{4}\) (c) \(\mathrm{SF}_{4}\) (d) \(\left[\mathrm{ClO}_{3}\right]^{-}\)

Hydrolysis of \(\mathrm{NCl}_{3}\) gives \(\mathrm{NH}_{3}\) and \(\mathrm{X}\). Which of the following is \(\mathrm{X} ?\) (a) \(\mathrm{HClO}_{4}\) (b) \(\mathrm{HClO}_{3}\) (c) \(\mathrm{HOCl}\) (d) \(\mathrm{HClO}_{2}\)

Which of the following is the strongest acid? (a) \(\mathrm{ClO}_{3}(\mathrm{OH})\) (b) \(\mathrm{ClO}_{2}(\mathrm{OH})\) (c) \(\mathrm{SO}(\mathrm{OH})_{2}\) (d) \(\mathrm{SO}_{2}(\mathrm{OH})_{2}\)

Which of the following is most stable? (a) \(\mathrm{HI}\) (b) \(\mathrm{HCl}\) (c) \(\mathrm{HBr}\) (d) HF

Which is the best description of the behaviour of bromine in the reaction given below? \(\mathrm{H}_{2} \mathrm{O}+\mathrm{Br}_{2} \longrightarrow \mathrm{HOBr}+\mathrm{HBr}\) (a) reduced only (b) oxidized only (c) both oxidized and reduced (d) proton acceptor only

Select the correct statement. (a) \(\mathrm{ClO}_{2}\) is the anhydride of \(\mathrm{HClO}_{2}\) and \(\mathrm{HClO}_{3}\) (b) \(\mathrm{I}_{2} \mathrm{O}_{5}\) is used in the quantitative estimation of \(\mathrm{CO}\) (c) \(\mathrm{Cl}_{2} \mathrm{O}\) and \(\mathrm{ClO}_{2}\) are used as bleaching agents and as germicides (d) all of the these are correct

Bleaching action of chlorine occurs in the presence of (a) moisture (b) sunlight (c) \(\mathrm{O}_{2}\) (d) dry air

Fluorine oxidizes \(\mathrm{HSO}_{4}^{-}\)to \(\ldots \ldots\) (a) \(\mathrm{SO}_{2}\) (b) \(\mathrm{S}_{4} \mathrm{O}_{6}^{2-}\) (c) \(\mathrm{S}_{2} \mathrm{O}_{3}^{2-}\) (d) \(\mathrm{S}_{2} \mathrm{O}_{8}^{2-}\)

\(\mathrm{Cl}_{2} \mathrm{O}\) is best prepared by passing dry (a) hydrogen chloride and oxygen over hot silver oxide (b) chlorine gas over hot \(\mathrm{HgO}\) (c) chlorine and oxygen over hot silver chlorate (d) hydrogen chloride over phosphorus pentoxide

\(\mathrm{SO}_{2}\) acts as a temporary bleaching agent but \(\mathrm{Cl}_{2}\) acts as a permanent bleaching agent. Why? (a) \(\mathrm{Cl}_{2}\) bleaches due to oxidation but \(\mathrm{SO}_{2}\) bleaches due to reduction (b) \(\mathrm{Cl}_{2}\) bleaches due to reduction but \(\mathrm{SO}_{2}\) bleaches due to oxidation (c) both (a) and (b) (d) none of these

Which one of the following represents the reaction between fluorine and cold dilute \(\mathrm{NaOH} ?\) (a) \(2 \mathrm{~F}_{2}+2 \mathrm{NaOH} \longrightarrow 2 \mathrm{NaF}+\mathrm{OF}_{2}+\mathrm{H}_{2} \mathrm{O}\) (b) \(\mathrm{F}_{2}+2 \mathrm{NaOH} \longrightarrow \mathrm{NaF}+\mathrm{NaOF}+\mathrm{H}_{2} \mathrm{O}\) (c) \(3 \mathrm{~F}_{2}+\mathrm{NaOH} \longrightarrow 5 \mathrm{NaF}+\mathrm{NaFO}_{3}\) (d) \(2 \mathrm{~F}_{2}^{2}+4 \mathrm{NaOH} \longrightarrow 4 \mathrm{NaF}+2 \mathrm{H}_{2} \mathrm{O}\)

Fluorine is obtained by the interaction of \(\mathrm{K}_{2} \mathrm{MnF}_{6}\) with Lewis acid \(\mathrm{SbF}_{5}\) because of the (a) acidalysis of \(\mathrm{MnF}_{4}\) (b) ionization of \(\mathrm{MnF}_{4}\) (c) decomposition of \(\mathrm{SbF}_{6}\) (d) decomposition of \(\mathrm{MnF}_{4}\)

Which of the following is used during the preparation of fluorine by Whytlaw- Gray method? (a) aqueous HF (b) molten \(\mathrm{KHF}_{2}\) (c) \(\mathrm{NH}_{4} \mathrm{~F}\) (d) aqueous KF

Which of the following are formed when \(\mathrm{BCl}_{3}\) is treated with \(\mathrm{NH}_{3}\). (a) \(\mathrm{B}\left(\mathrm{NH}_{2}\right)_{3}\) (b) \(\mathrm{B}_{2}\left(\mathrm{NH}_{3}\right)_{2}\) (c) \(\mathrm{BN}\) (d) All of these

Bleaching powder reacts with a few drops of concentrated \(\mathrm{HCl}\) to give (a) oxygen (b) calcium oxide (c) chlorine (d) hypochlorous acid

When chlorine is passed over dry slaked lime at room temperature, the main reaction product is (a) \(\mathrm{CaCl}_{2}\) (b) \(\mathrm{Ca}(\mathrm{OCl})_{2}\) (c) \(\mathrm{Ca}\left(\mathrm{ClO}_{2}\right)_{2}\) (d) \(\mathrm{CaOCl}_{2}\)

In the manufacture of bromine from sea water, the mother liquor containing bromides is treated with (a) chlorine (b) iodine (c) sulphur dioxide (d) carbon dioxide

Bleaching powder is used as a disinfectant for purification of water. When water-borne germs are killed, the disinfectant activity is destroyed. This is due to its disproportionation into (a) \(\mathrm{CaCl}_{2}\) and \(\mathrm{Ca}\left(\mathrm{ClO}_{3}\right)_{2}\) (b) \(\mathrm{CaO}, \mathrm{Cl}_{2}\) and \(\mathrm{CaCl}_{2}\) (c) \(\mathrm{CaO}\) and \(\mathrm{Cl}_{2}\) (d) \(\mathrm{CaCl}_{2}\) and \(\mathrm{Cl}_{2}\)

When water is allowed to freeze in the presence of Ar, Kr or Xe under pressure then (a) atoms to noble gas (G) get trapped in the crystal lattice of ice giving clathrates corresponding to the composition 8G. \(26 \mathrm{H}_{2} \mathrm{O}\) (b) these are called noble gas hydrates (c) both are correct here (d) all are incorrect here

Consider the following reaction: \(6 \mathrm{NaOH}+3 \mathrm{Cl}_{2} \longrightarrow 5 \mathrm{NaCl}+\mathrm{A}+3 \mathrm{H}_{2} \mathrm{O}\) What is the oxidation number of chlorine in 'A'? (a) \(-1\) (b) \(+1\) (c) \(+3\) (d) \(+5\)

In the presence of cobalt chloride ( \(\mathrm{CoCl}_{2}\) ), bleaching powder decomposes to form (a) \(\mathrm{Cl}_{2} \mathrm{O}\) and \(\mathrm{CaO}\) (b) \(\mathrm{CaCO}_{3}\) and \(\mathrm{O}_{3}\) (c) \(\mathrm{CaCl}_{2}\) and \(\mathrm{O}_{2}\) (d) \(\mathrm{ClO}_{2}\) and \(\mathrm{CaO}\)

Bond dissociation energies of HF, HCl, HBr follows the order \(\ldots \ldots .\) (a) \(\mathrm{HBr}>\mathrm{HCl}>\mathrm{HF}\) (b) \(\mathrm{HCl}>\mathrm{HBr}>\mathrm{HF}\) (c) \(\mathrm{HF}>\mathrm{HBr}>\mathrm{HCl}\) (d) \(\mathrm{HF}>\mathrm{HCl}>\mathrm{HBr}\)

Which electrolyte is used in the electrolytic method of preparation of fluorine? (a) \(\mathrm{KHF}_{2}+\mathrm{LiF}\) (b) \(\mathrm{CaCl}_{2}+\mathrm{KF}\) (c) \(\mathrm{KF}+\mathrm{LiHF}_{2}\) (d) \(\mathrm{NaF}+\mathrm{CaCl}_{2}\)

Which of the following is the strongest oxidizing agent? (a) \(\mathrm{F}_{2}\) (b) \(\mathrm{Cl}_{2}\) (c) \(\mathrm{Br}_{2}\) (d) \(\mathrm{I}_{2}\)

Which one of the following order is correct for the bond energies of halogen molecules? (a) \(\mathrm{Cl}_{2}>\mathrm{Br}_{2}>\mathrm{I}_{2}\) (b) \(\mathrm{Br}_{2}>\mathrm{Cl}_{2}>\mathrm{I}_{2}\) (c) \(\mathrm{I}_{2}>\mathrm{Cl}_{2}>\mathrm{Br}_{2}\) (d) \(\mathrm{I}_{2}>\mathrm{Br}_{2}>\mathrm{Cl}_{2}\)

HI can be prepared by all the following methods except (a) \(\mathrm{I}_{2}+\mathrm{H}_{2} \mathrm{~S}\) (b) \(\mathrm{PI}_{3}+\mathrm{H}_{2} \mathrm{O}\) (c) \(\mathrm{KI}+\mathrm{H}_{2} \mathrm{SO}_{4}\) (d) \(\mathrm{H}_{2}+\mathrm{I}_{2} \stackrel{\mathrm{Pt}}{\longrightarrow}\)

Which among the following is paramagnetic? (a) \(\mathrm{ClO}_{2}\) (b) \(\mathrm{Cl}_{2} \mathrm{O}_{6}\) (c) \(\mathrm{Cl}_{2} \mathrm{O}\) (d) \(\mathrm{Cl}_{2} \mathrm{O}_{7}\)

Which of the following oxides of chlorine is obtained by passing dry chlorine over silver chlorate at \(90^{\circ} \mathrm{C} ?\) (a) \(\mathrm{ClO}_{4}\) (b) \(\mathrm{ClO}_{3}\) (c) \(\mathrm{Cl}_{2} \mathrm{O}\) (d) \(\mathrm{ClO}_{2}\)

Chlorine acts as a bleaching agent only in presence of (a) sunlight (b) pure oxygen (c) dry air (d) moisture

Which one of the following pairs of reactants does not form oxygen when they react with each other? (a) \(\mathrm{Cl}_{2}, \mathrm{NaOH}\) solution (cold, dilute) (b) \(\mathrm{F}_{2}, \mathrm{NaOH}\) solution (hot, conc.) (c) \(\mathrm{F}_{2} \mathrm{H}_{2} \mathrm{O}\) (d) \(\mathrm{CaOCl}_{2}, \mathrm{H}_{2} \mathrm{SO}_{4}\) (dilute, small amount)

What is the correct order of occurrence (\% by weight) in air of \(\mathrm{Ne}, \mathrm{Ar}, \mathrm{Kr} ?\) (a) \(\mathrm{Ne}>\mathrm{Ar}>\mathrm{Kr}\) (b) \(\mathrm{Ar}>\mathrm{Ne}>\mathrm{Kr}\) (c) \(\mathrm{Ar}>\mathrm{Kr}>\mathrm{Ne}\) (d) \(\mathrm{Ne}>\mathrm{Kr}<\mathrm{Ar}\)

Noble gases do not react with other elements because (a) the size is completely paired up and has stable electrons shells (b) the size of their atoms is very small (c) they are found in abundance (d) they are monoatomic

In the Dewar's method of separation of noble gases, the mixture of noble gases is kept in contact with coconut charcoal at \(173 \mathrm{~K}\). Which one of the following gaseous mixtures is not adsorbed on to the charcoal? (a) \(\mathrm{He}, \mathrm{Ne}\) (b) \(\mathrm{Xe}, \mathrm{Kr}\) (c) \(\mathrm{Ar}, \mathrm{Kr}\) (d) \(\mathrm{Xe}, \mathrm{Ar}\)

Noble gases are sparingly soluble in water, owing to (a) hydrogen bonding (b) dipole-dipole interactions (c) dipole-induced dipole interactions (d) induced dipole-instantaneous dipole interactions

Which of the following statements is false? (a) \(\mathrm{He}_{2}\) does not exist (b) radon is obtained from the decay of radium (c) the most abundant rare gas found in the atmosphere is helium. (d) xenon is the most reactive among the rare gases

The ease of liquefaction of noble gases increase in the order (a) \(\mathrm{Ar}>\mathrm{Kr}>\mathrm{Xe}>\mathrm{Ne}>\mathrm{He}\) (b) \(\mathrm{Xe}>\mathrm{Kr}>\mathrm{Ne}>\mathrm{Ar}>\mathrm{He}\) (c) \(\mathrm{Kr}>\mathrm{Xe}>\mathrm{He}>\mathrm{Ne}>\mathrm{Ar}\) (d) \(\mathrm{He}>\mathrm{Ne}>\mathrm{Ar}>\mathrm{Kr}>\mathrm{Xe}\)

Which of the following gas mixtures is used by divers inside the sea? (a) \(\mathrm{O}_{2}+\mathrm{Ar}\) (b) \(\mathrm{O}_{2}+\mathrm{He}\) (c) \(\mathrm{O}_{2}+\mathrm{Xe}\) (d) \(\mathrm{O}_{2}+\mathrm{N}_{2}\)

What are the products formed in the reaction of xenon hexafluoride with silicon dioxide? (a) \(\mathrm{XeO}_{3}+\mathrm{SiF}_{2}\) (b) \(\mathrm{XeOF}_{4}+\mathrm{SiF}_{4}\) (c) \(\mathrm{XeSiO}_{4}+\mathrm{HF}\) (d) \(\mathrm{XeF}_{2}+\mathrm{SiF}_{4}\)

Which of the following is a correct pair with respect to molecular formula of a xenon compound and the hybridization state of xenon in it? (a) \(\mathrm{XeF}_{2}, \mathrm{sp}\) (b) \(\mathrm{XeF}_{4}, \mathrm{sp}^{2}\) (c) \(\mathrm{XeF}_{4}, \mathrm{sp}^{3}\) (d) \(\mathrm{XeF}_{2}, \mathrm{sp}^{3} \mathrm{~d}\)

The increase in boiling points of noble gases from He to Xe is due to the (a) increase in atomic volume (b) increase in electron affinity (c) increase in polarizability (d) decrease in ionization energy

Which of the following is an explosive compound? (a) \(\mathrm{XeOF}_{2}\) (b) \(\mathrm{XeF}_{2}\) (c) \(\mathrm{XeO}_{3}\) (d) \(\mathrm{XeOF}_{4}\)

\(\mathrm{B}(\mathrm{OH})_{3}+\mathrm{NaOH} \rightleftharpoons \mathrm{NaBO}_{2}+\mathrm{Na}\left[\mathrm{B}(\mathrm{OH})_{4}\right]+\mathrm{H}_{2} \mathrm{O}\) How can this reaction be made to proceed in forward direction? (a) addition of cis- 1,2 -diol (b) addition of borax (c) addition of trans- 1,2 -diol (d) addition of \(\mathrm{Na}_{2} \mathrm{HPO}_{4}\)

\(\mathrm{H}_{2} \mathrm{SO}_{4}\) is not used for the preparation of \(\mathrm{CO}_{2}\) from marble chips because (a) calcium sulphate is sparingly soluble and get deposited on marble chips and stops the reaction (b) it does not react (c) the reaction is vigorous (d) huge amount of heat is evolved

Oxalic acid is heated with concentrated \(\mathrm{H}_{2} \mathrm{SO}_{4} .\) When the resultant gases are passed over red hot carbon, \(\mathrm{X}\) is obtained. \(\mathrm{X}\) is (a) \(\mathrm{CO}\) (b) \(\mathrm{CO}_{2}\) (c) \(\mathrm{C}_{2} \mathrm{H}_{4}\) (d) \(\mathrm{CH}_{4}\)

Borax is converted into B by following steps Borax \(\stackrel{\mathrm{A}}{\longrightarrow} \mathrm{H}_{3} \mathrm{BO}_{3} \stackrel{\Delta}{\longrightarrow} \mathrm{B}_{2} \mathrm{O}_{3} \quad \mathrm{~B} \stackrel{\mathrm{B}}{\longrightarrow}\) Product Reagents \(\mathrm{A}\) and \(\mathrm{B}\) are (a) acid, \(\mathrm{Fe}\) (b) acid, \(\mathrm{Mg}\) (c) acid, \(\mathrm{Sn}\) (d) acid, Al

Consider the following transformations: (1) \(\mathrm{XeF}_{6}+\mathrm{NaF} \longrightarrow \mathrm{Na}^{+}\left[\mathrm{XeF}_{7}\right]^{-}\) (2) \(2 \mathrm{PCl}_{5}(\mathrm{~s}) \longrightarrow\left[\mathrm{PCl}_{4}\right]^{+}\left[\mathrm{PCl}_{6}\right]^{-}\) (3) \(\left[\mathrm{Al}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}+\mathrm{H}_{2} \mathrm{O} \longrightarrow\) \(\left[\mathrm{Al}\left(\mathrm{H}_{2} \mathrm{O}\right)_{5} \mathrm{OH}\right]^{2+}+\mathrm{H}_{3} \mathrm{O}^{+}\) The possible transformations are (a) 1,2 and 3 (b) 1 and 3 only (c) 1 and 2 only (d) 2 only

White phosphorus \(\left(\mathrm{P}_{4}\right)\) has 1\. six P-P sigma bonds 2\. four P-P single bonds 3\. four lone pairs of electrons 4\. PPP angle of \(60^{\circ}\) (a) \(1,2,3\) (b) \(2,3,4\) (c) \(1,3,4\) (d) all are correct

\(\mathrm{HBr}\) and HI reduce sulphuric acid, \(\mathrm{HCl}\) can reduce \(\mathrm{KMnO}_{4}\) and HF can reduce (a) \(\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) (b) \(\mathrm{KMnO}_{4}\) (c) \(\mathrm{H}_{2} \mathrm{SO}_{4}\) (d) none of the above

The number of P-O-P bridges in the structure of phosphorus pentoxide and phosphorus trioxide are respectively. (a) 5,5 (b) 5,6 (c) 6,5 (d) 6,6