Chapter 22

The lanthanoid that does NOT show \(+4\) oxidation state is: (a) Dy (b) \(\mathrm{Ce}\) (c) Eu (d) \(\mathrm{Tb}\)

The incorrect statement is : (a) Manganate and permanganate ions are tetrahedral (b) In manganate and permanganate ions, the \(\pi\)-bonding takes place by overlap of \(p\)-orbitals of oxygen and \(d\)-orbitals of manganese (c) Manganate and permanganate ions are paramagnetic (d) Manganate ion is green in colour and permanganate ion is purple in colour

Mischmetal is an alloy consisting mainly of: (a) lanthanoid metals (b) actinoid and transition metals (c) lanthanoid and actinoid metals (d) actinoid metals

The third ionization enthalpy is minimum for: (a) \(\mathrm{Co}\) (b) \(\mathrm{Fe}\) (c) Ni (d) \(\mathrm{Mn}\)

The correct electronic configuration and spin-only magnetic moment (BM) of \(\mathrm{Gd}^{3+}(\mathrm{Z}=64)\), respectively, are: (a) \([\mathrm{Xe}] 4 f^{7}\) and \(8.9\) (b) \([\mathrm{Xe}] 4 f^{7}\) and \(7.9\) (c) \([\mathrm{Xe}] 5 f^{7}\) and \(8.9\) (d) \([\mathrm{Xe}] 5 f^{7}\) and \(7.9\)

The electronic configurations of bivalent europium and trivalent cerium are: (atomic number : \(\mathrm{Xe}=54, \mathrm{Ce}=58, \mathrm{Eu}=63\) ) (a) \([\mathrm{Xe}] 4 f^{2}\) and \([\mathrm{Xe}] 4 f^{7}\) (b) \([\mathrm{Xe}] 4 f^{7}\) and \([\mathrm{Xe}] 4 f^{1}\) (c) \([\mathrm{Xe}] 4 f^{7} 6 \mathrm{~s}^{2}\) and \([\mathrm{Xe}] 4 f^{2} 6 \mathrm{~s}^{2}\) (d) \([\mathrm{Xe}] 4 f^{4}\) and \([\mathrm{Xe}] 4 f^{9}\)

Thermal decomposition of a Mn compound (X) at \(513 \mathrm{~K}\) results in compound \(\mathrm{Y}, \mathrm{MnO}_{2}\) and a gaseous product. \(\mathrm{MnO}_{2}\) reacts with \(\mathrm{NaCl}\) and concentrated \(\mathrm{H}_{2} \mathrm{SO}_{4}\) to give a pungent gas \(\mathrm{Z} . \mathrm{X}, \mathrm{Y}\), and \(\mathrm{Z}\), respectively, are: (a) \(\mathrm{KMnO}_{4}, \mathrm{~K}_{2} \mathrm{MnO}_{4}\) and \(\mathrm{Cl}_{2}\) (b) \(\mathrm{K}_{2} \mathrm{MnO}_{4}, \mathrm{KMnO}_{4}\) and \(\mathrm{SO}_{2}\) (c) \(\mathrm{K}_{3} \mathrm{MnO}_{4}, \mathrm{~K}_{2} \mathrm{MnO}_{4}\) and \(\mathrm{Cl}_{2}\) (d) \(\mathrm{K}_{2} \mathrm{MnO}_{4}, \mathrm{KMnO}_{4}\) and \(\mathrm{Cl}_{2}\)

The maximum number of possible oxidation states of actinoides are shown by: (a) Nobelium (No) and lawrencium (Lr) (b) Actinium (Ac) and thorium (Th) (c) Berkelium (Bk) and californium (Cf) (d) Neptunium (Np) and plutonium (Pu)

The lanthanide ion that would show colour is : (a) \(\mathrm{Gd}^{3+}\) (b) \(\mathrm{Sm}^{3+}\) (c) \(\mathrm{La}^{3+}\) (d) \(\mathrm{Lu}^{3+}\)

The INCORRECT statement is : (a) the gemstone, ruby, has \(\mathrm{Cr}^{3+}\) ions occupying the octahedral sites of beryl. (b) the spin-only magnetic moment of \(\left[\mathrm{Ni}\left(\mathrm{NH}_{3}\right)_{4}\left(\mathrm{H}_{2} \mathrm{O}\right)_{2}\right]^{2+}\) is \(2.83 \mathrm{BM}\). (c) the color of \(\left[\mathrm{CoCl}\left(\mathrm{NH}_{3}\right)_{5}\right]^{2+}\) is violet as it absorbs the yellow light. (d) the spin-only magnetic moments of \(\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}\) and \(\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}\) are nearly similar.

The correct order of atomic radii is : (a) \(\mathrm{N}>\mathrm{Ce}>\mathrm{Eu}>\mathrm{Ho}\) (b) \(\mathrm{Ho}>\mathrm{N}>\mathrm{Eu}>\mathrm{Ce}\) (c) \(\mathrm{Ce}>\mathrm{Eu}>\mathrm{Ho}>\mathrm{N}\) (d) \(\mathrm{Eu}>\mathrm{Ce}>\mathrm{Ho}>\mathrm{N}\)

The statement that is INCORRECT about the interstitial compounds is : (a) they are chemically reactive. (b) they are very hard. (c) they have metallic conductivity. (d) they have high melting points.

The effect of lanthanoid contraction in the lanthanoid series of elements by and large means: (a) increase in both atomic and ionic radii (b) decrease in atomic radii and increase in ionic radii (c) decrease in both atomic and ionic radii (d) increase in atomic radii and decrease in ionic radii

The element that usually does NOT show variable oxidation states is: (a) \(\mathrm{Cu}\) (b) Ti (c) \(\mathrm{Sc}\) (d) V

The transition element that has lowest enthalpy of atomisation is: (a) \(\mathrm{Fe}\) (b) \(\mathrm{Cu}\) (c) V (d) \(\mathrm{Zn}\)

In the following reactions, \(\mathrm{ZnO}\) is respectively acting as a/an: (i) \(\mathrm{ZnO}+\mathrm{Na}_{2} \mathrm{O} \rightarrow \mathrm{Na}_{2} \mathrm{ZnO}_{2}\) (ii) \(\mathrm{ZnO}+\mathrm{CO}_{2} \rightarrow \mathrm{ZnCO}_{3}\) (a) base and acid (b) base and base (c) acid and acid (d) acid and base

Which of the following ions does not liberate hydrogen gas on reaction with dilute acids ? (a) \(\mathrm{Ti}^{2+}\) (b) \(\mathrm{V}^{2+}\) (c) \(\mathrm{Cr}^{2+}\) (d) \(\mathrm{Mn}^{2+}\)

Which of the following combination will produce \(\mathrm{H}_{2}\) gas? (a) Fe metal and conc. \(\mathrm{HNO}_{3}\) (b) Cu metal and conc. \(\mathrm{HNO}_{3}\) (c) \(\mathrm{Zn}\) metal and \(\mathrm{NaOH}(\mathrm{aq})\) (d) Au metal and \(\mathrm{NaCN}(\mathrm{aq})\) in the presence of air

The reaction of zinc with dilute and concentrated nitric acid, respectively, produces: (a) \(\mathrm{NO}\) and \(\mathrm{N}_{2} \mathrm{O}\) (b) \(\mathrm{NO}_{2}\) and \(\mathrm{N}_{2} \mathrm{O}\) (c) \(\mathrm{N}_{2} \mathrm{O}\) and \(\mathrm{NO}_{2}\) (d) \(\mathrm{NO}_{2}\) and \(\mathrm{NO}\)

Which of the following compounds is metallic and ferromagnetic? (a) \(\mathrm{VO}_{2}\) (b) \(\mathrm{MnO}_{2}\) (c) \(\mathrm{TiO}_{2}\) (d) \(\mathrm{CrO}_{2}\)

The transition metal ions responsible for colour in ruby and emerald are, respectively: (a) \(\mathrm{Co}^{3+}\) and \(\mathrm{Cr}^{3+}\) (b) \(\mathrm{Co}^{3+}\) and \(\mathrm{Co}^{3+}\) (c) \(\mathrm{Cr}^{3+}\) and \(\mathrm{Cr}^{3+}\) (d) \(\mathrm{Cr}^{3+}\) and \(\mathrm{Co}^{3+}\)

When concentrated \(\mathrm{HCl}\) is added to an aqueous solution of \(\mathrm{CoCl}_{2}\), its colour changes from reddish pink to deep blue. Which complex ion gives blue colour in this reaction? (a) \(\left[\mathrm{CoCl}_{4}\right]^{2-}\) (b) \(\left[\mathrm{CoCl}_{6}\right]^{3-}\) (c) \(\left[\mathrm{CoCl}_{6}\right]^{4-}\) (d) \(\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}\)

The equation which is balanced and represents the correct product(s) is: (a) \(\mathrm{Li}_{2} \mathrm{O}+2 \mathrm{KCl} \longrightarrow 2 \mathrm{LiCl}+\mathrm{K}_{2} \mathrm{O}\) (b) \(\left[\mathrm{CoCl}\left(\mathrm{NH}_{3}\right)_{5}\right]^{+}+5 \mathrm{H}^{+} \longrightarrow \mathrm{Co}^{2+}+5 \mathrm{NH}_{4}^{+}+\mathrm{Cl}^{-}\) (c) \(\left[\mathrm{Mg}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}+(\mathrm{EDTA})^{4-}\) \(\stackrel{\text { excess } \mathrm{NaOH}}{\longrightarrow}[\mathrm{Mg}(\mathrm{EDTA})]^{2+}+6 \mathrm{H}_{2} \mathrm{O}\) (d) \(\mathrm{CuSO}_{4}+4 \mathrm{KCN} \longrightarrow \mathrm{K}_{2}\left[\mathrm{Cu}(\mathrm{CN})_{4}\right]+\mathrm{K}_{2} \mathrm{SO}_{4}\)

Which series of reactions correctly represents chemical reactions related to iron and its compound? (a) \(\mathrm{Fe} \stackrel{\mathrm{dil} \cdot \mathrm{H}_{2} \mathrm{SO}_{4}}{\longrightarrow} \mathrm{FeSO}_{4} \stackrel{\mathrm{H}_{2} \mathrm{SO}_{4}, \mathrm{O}_{2}}{\longrightarrow}\) \(\mathrm{Fe}_{2}\left(\mathrm{SO}_{4}\right)_{3} \stackrel{\text { heat }}{\longrightarrow} \mathrm{Fe}\) (b) \(\mathrm{Fe} \stackrel{\mathrm{O}_{2}, \text { heat }}{\longrightarrow} \mathrm{FeO} \stackrel{\text { dil. } \mathrm{H}_{2} \mathrm{SO}_{4}}{\longrightarrow}\) \(\mathrm{FeSO}_{4} \stackrel{\text { heat }}{\longrightarrow} \mathrm{Fe}\) (c) \(\mathrm{Fe} \stackrel{\mathrm{Cl}_{2}, \text { heat }}{\longrightarrow} \mathrm{FeCl}_{3} \stackrel{\text { heat, air }}{\longrightarrow} \mathrm{FeCl}_{2} \stackrel{\mathrm{Zn}}{\longrightarrow} \mathrm{Fe}\) (d) \(\mathrm{Fe} \stackrel{\mathrm{O}_{2} \text {, heat }}{\longrightarrow} \mathrm{Fe}_{3} \mathrm{O}_{4} \stackrel{\mathrm{CO}, 600^{\circ} \mathrm{C}}{\longrightarrow}\) \(\mathrm{FeO} \stackrel{\mathrm{CO}, 700^{\circ} \mathrm{C}}{\longrightarrow} \mathrm{Fe}\)

Which one of the following exhibits the large number of oxidation states? (a) Ti (22) (b) V (23) (c) \(\operatorname{Cr}(24)\) (d) \(\operatorname{Mn}(25)\)

Which of the following is not formed when \(\mathrm{H}_{2} \mathrm{~S}\) reacts with acidic \(\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) solution? (a) \(\mathrm{CrSO}_{4}\) (b) \(\mathrm{Cr}_{2}\left(\mathrm{SO}_{4}\right)_{3}\) (c) \(\mathrm{K}_{2} \mathrm{SO}_{4}\) (d) \(\mathrm{S}\)

Four successive members of the first row transition elements are listed below with atomic numbers. Which one of them is expected to have the highest \(\mathrm{E}_{\mathrm{M}}^{\circ} 3+\mathrm{M}^{2+}\) value ? (a) \(\operatorname{Cr}(\mathrm{Z}=24)\) (b) \(\operatorname{Mn}(Z=25)\) (c) \(\mathrm{Fe}(\mathrm{Z}=26)\) (d) \(\operatorname{Co}(\mathrm{Z}=27)\)

When a small amount of \(\mathrm{KMnO}_{4}\) is added to concentrated \(\mathrm{H}_{2} \mathrm{SO}_{4}\), a green oily compound is obtained which is highly explosive in nature. Compound may be : (a) \(\mathrm{MnSO}_{4}\) (b) \(\mathrm{Mn}_{2} \mathrm{O}_{7}\) (c) \(\mathrm{MnO}_{2}\) (d) \(\mathrm{Mn}_{2} \mathrm{O}_{3}\)

The element with which of the following outer electron configuration may exhibit the largest number of oxidation states in its compounds: (a) \(3 d^{5} 4 s^{2}\) (b) \(3 d^{8} 4 s^{2}\) (c) \(3 d^{7} 4 s^{2}\) (d) \(3 d^{6} 4 s^{2}\)

The colour of light absorbed by an aqueous solution of \(\mathrm{CuSO}_{4}\) is: (a) orange-red (b) blue-green (c) yellow (d) violet

Native silver metal forms a water soluble complex with a dilute aqueous solution of \(\mathrm{NaCN}\) in the presence of(a) nitrogen (b) oxygen (c) carbon dioxide (d) argon

\(\mathrm{CuSO}_{4}\) decolourises on addition of \(\mathrm{KCN}\), the product formed is (a) \(\mathrm{Cu}^{2+}\) get reduced to form \(\left[\mathrm{Cu}(\mathrm{CN})_{4}\right]^{3-}\) (b) \(\left[\mathrm{Cu}(\mathrm{CN})_{4}\right]^{2-}\) (c) \(\mathrm{CuCN}\) (d) \(\mathrm{Cu}(\mathrm{CN})_{2}\)

Which pair of compounds is expected to show similar colour in aqueous medium? (a) \(\mathrm{FeCl}_{2}\) and \(\mathrm{CuCl}_{2}\) (b) \(\mathrm{VOCl}_{2}\) and \(\mathrm{CuCl}_{2}\) (c) \(\mathrm{VOCl}_{2}\) and \(\mathrm{FeCl}_{2}\) (d) \(\mathrm{FeCl}_{2}\) and \(\mathrm{MnCl}_{2}\)

\(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) on heating liberates a gas. The same gas will be obtained by (a) heating \(\mathrm{NH}_{4} \mathrm{NO}_{2}\) (b) heating \(\mathrm{NH}_{4} \mathrm{NO}_{3}\) (c) treating \(\mathrm{H}_{2} \mathrm{O}_{2}\) with \(\mathrm{NaNO}_{2}\) (d) treating \(\mathrm{Mg}_{3} \mathrm{~N}_{2}\) with \(\mathrm{H}_{2} \mathrm{O}\)

The product of oxidation of \(\mathrm{I}^{-}\)with \(\mathrm{MnO}_{4}^{-}\)in alkaline medium is (a) \(\mathrm{IO}_{3}^{-}\) (b) \(\mathrm{I}_{2}\) (c) IO- (d) \(\mathrm{IO}_{4}^{-}\)

When \(\mathrm{MnO}_{2}\) is fused with \(\mathrm{KOH}\), a coloured compound is formed, the product and its colour is: (a) \(\mathrm{K}_{2} \mathrm{MnO}_{4}\), purple green (b) \(\mathrm{KMnO}_{4}\), purple (c) \(\mathrm{Mn}_{2} \mathrm{O}_{3}\), brown (d) \(\mathrm{Mn}_{3} \mathrm{O}_{4}\), black

Anhydrous ferric chloride is prepared by (a) heating hydrated ferric chloride at a high temperature in a stream of air (b) heating metallic iron in a stream of dry chlorine gas (c) reaction of metallic iron with hydrochloric acid (d) reaction of metallic iron with nitric acid

In the dichromate anion, (a) \(4 \mathrm{Cr}-\mathrm{O}\) bonds are equivalent (b) \(6 \mathrm{Cr}-\mathrm{O}\) bonds are equivalent (c) all \(\mathrm{Cr}-\mathrm{O}\) bonds are equivalent (d) all \(\mathrm{Cr}-\mathrm{O}\) bonds are nonequivalent

Which of the following compounds is expected to be coloured? (a) \(\mathrm{Ag}_{2} \mathrm{SO}_{4}\) (b) \(\mathrm{CuF}_{2}\) (c) \(\mathrm{MgF}_{2}\) (d) \(\mathrm{CuCl}\).

The number of moles of \(\mathrm{KMnO}_{4}\) that will be needed to react with one mole of sulphite ion in acidic solution is (a) \(\frac{2}{5}\) (b) \(\frac{3}{5}\) (c) \(\frac{4}{5}\) (d) 1

Ammonium dichromate is used in some fireworks. The green coloured powder blown in the air is (a) \(\mathrm{CrO}_{3}\) (b) \(\mathrm{Cr}_{2} \mathrm{O}_{3}\) (c) \(\mathrm{Cr}\) (d) \(\mathrm{CrO}\left(\mathrm{O}_{2}\right)\)

An aqueous solution of \(\mathrm{FeSO}_{4}, \mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3}\) and chrome alum is heated with excess of \(\mathrm{Na}_{2} \mathrm{O}_{2}\) and filtered. The materials obtained are : (a) a colourless filtrate and a green residue (b) a yellow filtrate and a green residue (c) a yellow filtrate and a brown residue (d) a green filtrate and a brown residue

Which compound does not dissolve in hot, dilute \(\mathrm{HNO}_{3} ?\) (a) \(\mathrm{HgS}\) (b) PbS (c) \(\mathrm{CuS}\) (d) \(\mathrm{CdS}\)

Which compound is formed when excess of \(\mathrm{KCN}\) is added to aqueous solution of copper sulphate? (a) \(\mathrm{Cu}(\mathrm{CN})_{2}\) (b) \(\mathrm{K}_{2}\left[\mathrm{Cu}(\mathrm{CN})_{4}\right]\) (c) \(\mathrm{K}\left[\mathrm{Cu}(\mathrm{CN})_{2}\right]\) (d) \(\mathrm{K}_{3}\left[\mathrm{Cu}(\mathrm{CN})_{4}\right]\)

Which one is solder? (a) \(\mathrm{Cu} \& \mathrm{~Pb}\) (b) \(\mathrm{Zn} \& \mathrm{Cu}\) (c) \(\mathrm{Pb}\) \& \(\mathrm{Sn}\) (d) \(\mathrm{Fe} \& \mathrm{Zn}\)

Zinc-copper couple that can be used as a reducing agent is obtained by: (a) mixing zinc dust and copper gauze (b) zinc coated with copper (c) copper coated with zinc (d) zinc and copper wires welded together

Iron is rendered passive by treatment with concentrated (a) \(\mathrm{H}_{2} \mathrm{SO}_{4}\) (b) \(\mathrm{H}_{3} \mathrm{PO}_{4}\) (c) \(\mathrm{HCl}\) (d) \(\mathrm{HNO}_{3}\)

Sodium thiosulphate is used in photography because of its (a) reducing behaviour (b) oxidising behaviour (c) complex forming behaviour (d) reaction with light

How many unpaired electrons are present in \(\mathrm{Ni}^{2+}\) ? (a) 0 (b) 2 (c) 4 (d) 8

Which of the following dissolve in hot conc. \(\mathrm{NaOH}\) solutio (a) \(\mathrm{Fe}\) (b) \(\mathrm{Zn}\) (c) \(\mathrm{Cu}\) (d) \(\mathrm{Ag}\)