Chapter 12

The process (es) requiring the absorption of energy is/ are : (a) \(\mathrm{Cl} \rightarrow \mathrm{Cl}^{-}\) (b) \(\mathrm{O}^{-} \rightarrow \mathrm{O}^{2-}\) (c) \(\mathrm{Fe}^{3+} \rightarrow \mathrm{Fe}^{2+}\) (d) \(\mathrm{Ar} \rightarrow \mathrm{Ar}\)

Increasing order of second ionization energy is (a) \(\mathrm{Ne}>\mathrm{O}>\mathrm{F}>\mathrm{N}>\mathrm{B}>\mathrm{C}>\mathrm{Be}\) (b) \(\mathrm{Be}<\mathrm{C}<\mathrm{B}<\mathrm{N}<\mathrm{F}<\mathrm{O}<\mathrm{Ne}\) (c) \(\mathrm{Be}<\mathrm{B}<\mathrm{C}<\mathrm{N}<\mathrm{O}<\mathrm{F}<\mathrm{Ne}\) (d) \(\mathrm{B}<\mathrm{C}<\mathrm{N}<\mathrm{O}<\mathrm{F}<\mathrm{Be}<\mathrm{Ne}\)

Decreasing order of electron affinity is (a) \(\mathrm{F}>\mathrm{Cl}>\mathrm{Br}>\mathrm{I}>\mathrm{S}>\mathrm{Si}\) (b) \(\mathrm{Si}>\mathrm{S}>\mathrm{F}>\mathrm{Cl}>\mathrm{Br}>\mathrm{I}\) (c) \(\mathrm{Cl}>\mathrm{F}>\mathrm{Br}>\mathrm{I}>\mathrm{S}>\mathrm{Si}\) (d) \(\mathrm{Cl}>\mathrm{F}>\mathrm{Br}>\mathrm{S}>\mathrm{Si}>\mathrm{I}\)

Which of the following is arranged in the order of decreasing electropositive character ? (a) \(\mathrm{Fe}, \mathrm{Mg}, \mathrm{Cu}\) (b) \(\mathrm{Mg}, \mathrm{Cu}, \mathrm{Fe}\) (c) \(\mathrm{Mg}, \mathrm{Fe}, \mathrm{Cu}\) (d) \(\mathrm{Cu}, \mathrm{Fe}, \mathrm{Mg}\)

An element has exceptional outer electronic configuration as \(4 \mathrm{~d}^{10} 5 \mathrm{~s}^{\circ}\). It belongs to

Match the following List-I List-II - \(\mathrm{Ti}^{3+}\) (p) Paramagnetic (a) (b) \(\mathrm{Cu}^{2+}\) (q) Coloured (c) \(\mathrm{Co}^{2+}\) (r) One un-paired electron ) (d) \(\mathrm{Zn}^{2+}\) (s) Diamagnetic

The correct order of atomic size of \(\mathrm{C}, \mathrm{N}, \mathrm{P}\) and \(\mathrm{S}\) follows the order (a) \(\mathrm{C}<\mathrm{N}<\mathrm{S}<\mathrm{P}\) (b) \(C

$$ \begin{aligned} &\text { Match the following }\\\ &\begin{array}{ll} \hline \text { Column-I } & \text { Column-II } \\ \hline \text { (a) } \mathrm{Ce}^{4+} & \text { (p) Oxidizing agent in volu- } \\\ \text { metric analysis } \\ \text { (b) } \mathrm{Nd}^{3+} & \text { (q) Misch metal } \\ \text { (c) } \mathrm{La}^{3+} & \text { (r) Colourless salts } \\ \begin{array}{ll} \text { (d) } \mathrm{Pr}^{3+} & \text { (s) Coloured glases for gog- } \\ \text { gles. } \end{array} \\ \hline \end{array} \end{aligned} $$

When the sample of copper with zinc impurity is to be purified by electrolysis, the appropriate electrodes are [2002] Cathode Anode \(\begin{array}{ll}\text { (a) pure zinc } & \text { pure copper }\end{array}\) (b) pure copper impure sample (c) impure zinc impure sample (d) impure sample pure copper

Match the following \begin{tabular}{c|c} Column-I & Column-II \end{tabular} (a) \(C>\mathrm{N}\) (p) More favourable (exothermic) electron affinity. (b) \(\mathrm{Se}>\mathrm{Br}\) (q) The higher first ionization energy. (c) \(\mathrm{Mg}>\mathrm{K}\) (r) The larger size (d) \(\mathrm{F}>\mathrm{Cl}\) (s) The higher electronegativity. (t) The higher number of valence electrons.

Number of electrons transferred in each case when \(\mathrm{KMnO}_{4}\) acts as an oxidizing agent to give \(\mathrm{MnO}_{2}\), \(\mathrm{Mn}^{2+}, \mathrm{Mn}(\mathrm{OH})_{2}\) and \(\mathrm{MnO}_{4}^{2-}\) are respectively \(\quad[\mathbf{2 0 0 2}]\) (a) \(1,3,4\) and 5 (b) \(4,3,1\) and 5 (c) \(5,4,3\) and 1 (d) \(3,5,4\) and 1

\begin{aligned} &\text { Match the following }\\\ &\begin{array}{ll} \hline \text { Column-I } & \text { Column-II } \\ \hline \text { (a) } \mathrm{Na}^{+}<\mathrm{F}^{-}<\mathrm{O}^{2-}<\mathrm{N}^{3-} & \text { (p) Electronegativity } \\ \text { (b) } \mathrm{Li}^{+}<\mathrm{Na}^{+}<\mathrm{K}^{+}<\mathrm{Rb}^{+}<\mathrm{Cs}^{+} & \text {(q) } \begin{array}{l} \text { Mobility of } \\ \text { hydrated ions } \end{array} \\ \text { (c) } \mathrm{O}<\mathrm{S}<\mathrm{F}<\mathrm{Cl} & \text { (r) } \text { Ionic size } \\ \text { (d) } \mathrm{Cl}^{-}<\mathrm{K}^{+}<\mathrm{Ca}^{2+}<\mathrm{Sc}^{3+} & \text { (s) Electron affinity } \\ \hline \end{array} \end{aligned}Reason: Fluorine has small size and high electronegativity.

The most stable ion is \([\mathbf{2 0 0 2}]\) (a) \(\left[\mathrm{Fe}(\mathrm{OH})_{5}\right]^{3-}\) (b) \(\left[\mathrm{FeCl}_{6}\right]^{3-}\) (c) \(\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{3-}\) (d) \(\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}\)

Most common oxidation states of \(\mathrm{Ce}\) are \(\quad\) [2002] (a) \(+3,+4\) (b) \(+2,+3\) (c) \(+2,+4\) (d) \(+3,+5\)

The atomic number of \(\mathrm{V}, \mathrm{Cr}, \mathrm{Mn}\) and \(\mathrm{Fe}\) are respectively \(23,24,25\) and 26 . which one of these may be expected to have the highest second ionization enthalpy? (a) \(\mathrm{Mn}\) (b) \(\mathrm{Fe}\) (c) \(\mathrm{Cr}\) (d) \(\mathrm{V}\)

What would happen when a solution of potassium chromate is treated with an excess of dilute nitric acid? (a) \(\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}\) and \(\mathrm{H}_{2} \mathrm{O}\) are formed (b) \(\mathrm{Cr}^{3+}\) and \(\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}\) are formed (c) \(\mathrm{CrO}_{4}^{2-}\) is oxidized to \(+7\) state to \(\mathrm{Cr}\) (d) \(\mathrm{CrO}_{4}^{2-}\) is reduced to \(+3\) state of \(\mathrm{Cr}\)

Assertion: The 4 f and 5 f- inner transition series of elements are placed separately at the bottom of the periodic table. Reason: (i) This prevents the undue expansion of the periodic table, i.e., maintains its structure. (ii) This preserve the principle of classification by keeping elements with similar properties in a single column.

The radius of \(\mathrm{La}^{3+}\) (atomic number \(=57\) ) is \(1.06 \AA\). Which one of the following given values will be closest to the radius of \(\mathrm{Lu}^{3+}\) (atomic number \(\left.=71\right)\) ? [2003] (a) \(0.85 \AA\) (b) \(1.06 \AA\) (c) \(1.40 \AA\) (d) \(1.60 \AA\)

Assertion: Manganese (atomic number 25) has a less favourable electron affinity than its neighbours on either side because Reason: The manganese has stable, [Ar] \(^{18} 3 \mathrm{~d}^{5} 4 \mathrm{~s}^{2}\) electrons configuration.

Assertion: The electron gain enthalpies have large negative values toward the upper right of the periodic table preceding the noble gases. Reason: The effective nuclear charge increases from left to right across a period and consequently it will be easier to add an electron to a smaller atom since the added electron on an average would be closer to the positively charged nucleus.

The number of pairs of elements which show diagonal relationship across the periodic table is \(. \mathrm{Li}-\mathrm{Mg}\); \(\mathrm{Be}-\mathrm{Al} ; \mathrm{B}-\mathrm{Si} ; \mathrm{K}-\mathrm{Sr} ; \mathrm{N}-\mathrm{S} ; \mathrm{Na}-\mathrm{Ca}\)

An element with atomic number 34 belongs to which period?

How many e are present in all s-sub shell of Br-atem.

How many of these elements are less electronegative than N-atom (No. only) F, O, C, B, Be, P, C, Si, Br

\(\mathrm{Ce}^{3+}, \mathrm{La}^{3+}, \mathrm{Pm}^{3+}\) and \(\mathrm{Yb}^{3+}\) have ionic radii in the in creasing order as (a) \(\mathrm{La}^{3+}<\mathrm{Ce}^{3+}<\mathrm{Pm}^{3+}<\mathrm{Y} \mathrm{b}^{3+}\) (b) \(\mathrm{Yb}^{3+}<\mathrm{Pm}^{3+}<\mathrm{Ce}^{3+}<\mathrm{La}^{3+}\) (c) \(\mathrm{La}^{3+}=\mathrm{Ce}^{3+}<\mathrm{Pm}^{3+}<\mathrm{Yb}^{3+}\) (d) \(\mathrm{Yb}^{3+}<\mathrm{Pm}^{3+}<\mathrm{La}^{3+}<\mathrm{Ce}^{3+}\)

The lanthanide contraction is responsible for the fact that \([\mathbf{2 0 0 5}]\) (a) \(\mathrm{Zr}\) and \(\mathrm{Y}\) have about the same radius (b) \(\mathrm{Zr}\) and \(\mathrm{Zn}\) have the same oxidation state (c) \(\mathrm{Zr}\) and Hf have about the same atomic radius (d) \(\mathrm{Zr}\) and \(\mathrm{Nb}\) have similar oxidation state

According to the periodic law of elements, the variation in properties of elements is related to their (a) atomic masses (b) nuclear masses (c) atomic numbers (d) nuclear neutron-proton number ratios

Which of the following factors may be regarded as the main cause of lanthanide contraction? \(\quad\) [2005] (a) poor shielding of one of 4 f electrons by another in the subshell (b) effective shielding of one of \(4 \mathrm{f}\) electrons by another in the subshell (c) poor shielding of 5 d-electrons by 4 f electrons (d) greater shielding of 5 d-electrons by 4 f electrons

A reduction in atomic sizes with increase in atomic number is a characteristic of element of \(\quad\) [2003] (a) high atomic masses (b) d-block (c) f-block (d) radioactive series

The IUPAC name of the coordination compound \(\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]\) is \([2005]\) (a) potassium hexacyanoferrate (III) (b) potassium hexacyanoferrate (II) (c) tripotassium hexacyaniron (II) (d) potassium hexacyanoiron (II)

A reduction in atomic sizes with increase in atomic number is a characteristic of element of \(\quad\) [2003] (a) high atomic masses (b) d-block (c) f-block (d) radioactive series

Which of the following cyano complexes would exhibit the lowest value of paramagnetic behaviour? [2005] (a) \(\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{3-}\) (b) \([\mathrm{Co}(\mathrm{CN})]^{3-}\) (c) \(\left[\mathrm{Mn}(\mathrm{CN})_{6}\right]^{3-}\) (d) \(\left[\mathrm{Cr}(\mathrm{CN})_{6}\right]^{3-}\)

The atomic numbers of \(\mathrm{V}, \mathrm{Cr}, \mathrm{Mn}\) and \(\mathrm{Fe}\) are respectively \(23,24,25\) and \(26 .\) Which one of these may be expected to have the highest second ionization enthalpy? (a) \(\mathrm{V}\) (b) \(\mathrm{Cr}\) (c) \(\mathrm{Mn}\) (d) FE

Lanthanoid contraction is caused due to (a) the appreciable shielding of outer electrons by \(4 \mathrm{f}\) electrons from the nuclear charge (b) the appreciable shielding on outer electrons by 5d-electrons from the nuclear charge (c) the same effective nuclear charge from Ce to Lu (d) the imperfect shielding of outer electrons by \(4 \mathrm{f}\) electrons from the nuclear charge

The radius of \(\mathrm{La}^{3+}\) (atomic number \(=57\) ) is \(1.06 \mathrm{~A}\). Which one of the following given values will be closest to the radius of \(\mathrm{Lu}^{3+}\) (atomic number \(=71\) )? [2003] (a) \(0.85 \mathrm{~A}\) (b) \(1.06 \mathrm{~A}\) (c) \(1.40 \mathrm{~A}\) (d) \(1.60 \mathrm{~A}\)

Larger number of oxidation states are exhibited by the actinoids than those by the lanthanoids, the main reason being \([2008]\) (a) 4 f-orbitals more diffused than the 5 f-orbitals (b) Lesser energy difference between \(5 \mathrm{f}\) and \(6 \mathrm{~d}\) than between \(4 \mathrm{f}\) and \(5 \mathrm{~d}\) orbitals (c) More energy difference between \(5 \mathrm{f}\) and \(6 \mathrm{~d}\) than between \(4 \mathrm{f}\) and \(5 \mathrm{~d}\) orbitals (d) More reactive nature of the actinoids than the lanthanoids.

Which one of the following is an amphoteric oxide? [2003] (a) \(\mathrm{ZnO}\) (b) \(\mathrm{Na}_{2} \mathrm{O}\) (c) SO. (d) \(\mathrm{B}_{2} \mathrm{O}_{.}\)

In context with the transition elements, which of the following statement is incorrect? (a) In the highest oxidation states, the transition metal show basic character and cationic complex. (b) In the highest oxidation states of the first five transition element (Sc to Mn), all the \(4 \mathrm{~s}\) and \(3 \mathrm{~d}\) electrons are used for bonding. (c) Once the \(\mathrm{d}^{5}\) configuration is exceeded, the tendency to involve all the \(3 \mathrm{~d}\) electrons in bonding decreases. (d) In addition to the normal oxidation states, the zero oxidation state is also shown by these elements in complex.

Which one the following sets of ions represents the collection of isoelectronic species? [2004] (a) \(\mathrm{Na}^{+}, \mathrm{Ca}^{2+}, \mathrm{Sc}^{3+}, \mathrm{F}-\) (b) \(\mathrm{K}^{+}, \mathrm{Cl}^{-}, \mathrm{Mg}^{2+}, \mathrm{Sc}^{3+}\) (c) \(\mathrm{K}^{+}, \mathrm{Ca}^{2+}, \mathrm{Sc}^{3+}, \mathrm{Cl}^{-}\) (d) \(\mathrm{Na}^{+}, \mathrm{Mg}^{2+}, \mathrm{Al}^{3+}, \mathrm{Cl}-\)

Knowing that the chemistry of lanthanoids (Ln) is dominated by its \(+3\) oxidation state, which of the following statements is incorrect? (a) The ionic sizes of Ln (III) decrease in general with increasing atomic number. (b) Ln (III) compounds are generally colourless. (c) Ln (III) hydroxides are mainly basic in character. (d) Because of the large size of the Ln (III) ions the bonding in its compounds is predominantly ionic in character.

Among \(\mathrm{Al}_{2} \mathrm{O}_{3}, \mathrm{SiO}_{2}, \mathrm{P}_{2} \mathrm{O}_{3}\) and \(\mathrm{SO}_{2}\) the correct order of acidic strength is [2004] (a) \(\mathrm{Al}_{2} \mathrm{O}_{3}<\mathrm{SiO}_{2}<\mathrm{P}_{2} \mathrm{O}_{3}<\mathrm{SO}_{2}\) (b) \(\mathrm{SO}_{2}<\mathrm{P}_{2} \mathrm{O}_{3}<\mathrm{SiO}_{2}<\mathrm{Al}_{2} \mathrm{O}_{3}\) (c) \(\mathrm{SiO}_{2}<\mathrm{SO}_{2}<\mathrm{Al}_{2} \mathrm{O}_{3}<\mathrm{P}_{2} \mathrm{O}_{3}\) (d) \(\mathrm{Al}_{2} \mathrm{O}_{3}<\mathrm{SiO}_{2}<\mathrm{SO}_{2}<\mathrm{P}_{2} \mathrm{O}_{3}\)

The outer electron configuration of Gd (atomic number \(=64\) ) is: (a) \(4 \mathrm{f}^{7} 5 \mathrm{~d}^{1} 6 \mathrm{~s}^{2}\) (b) \(4 \mathrm{f}^{3} 5 \mathrm{~d}^{2} 6 \mathrm{~s}^{2}\) (c) \(4 f^{8} 5 d^{\circ} 6 s^{2}\) (d) \(4 \mathrm{f}^{4} 5 \mathrm{~d}^{4} 6 \mathrm{~s}^{2}\)

The formation of the oxide ion \(\mathrm{O}^{2-}(\mathrm{g})\) require first an exothermic and then an endothermic step as shown below \(\mathrm{O}(\mathrm{g})+\mathrm{e}^{-} \longrightarrow \mathrm{O}^{-}(\mathrm{g}) ; \Delta \mathrm{H}^{\circ}=-142 \mathrm{~kJ} \mathrm{~mol}^{-1}\) \(\mathrm{O}^{-}(\mathrm{g})+\mathrm{e}^{-} \longrightarrow \mathrm{O}^{2-}(\mathrm{g}) ; \Delta \mathrm{H}^{0}=844 \mathrm{~kJ} \mathrm{~mol}^{-1}\) This is because (a) oxygen is more electronegative (b) oxygen has high electron affinity (c) \(\mathrm{O}^{-}\)ion has comparatively larger size than oxygen atom (d) \(\mathrm{O}^{-}\)ion will tend to resist the addition of another electron

In context of the lanthanoids, which of the follwoing statements is not correct? (a) Availability of 4 f electrons results in the formation of compound in \(+4\) state for all the members of the series. (b) There is a gradual decrease in the radii of the members with increasing atomic number in the series. (c) Because of similar properties the separation of lanthanoids is not easy (d) All the members exhibit \(+3\) oxidation state.

Which of the following ion has the highest value of ionic radius? (a) \(\mathrm{F}^{-}\) (b) \(\mathrm{O}^{2-}\) (c) \(\mathrm{B}^{3+}\) (d) \(\mathrm{Li}^{+}\)

The lanthanide contraction is responsible for the fact that (a) \(\mathrm{Zr}\), Hf have about the same radius (b) \(\mathrm{Zr}\), Y have about the same radius (c) \(\mathrm{Zr}\), Nb have same oxidation state (d) \(\mathrm{Zr}\), Zn have same oxidation state

Which of the following oxides is amphoteric in character? (a) \(\mathrm{SnO}_{2}\) (b) \(\mathrm{CO}_{2}\) (c) \(\mathrm{CaO}\) (d) \(\mathrm{SiO}_{2}\)

In which of the following arrangements, the order is not according to the property indicated against it? \([\mathbf{2 0 0 5}]\) (a) \(\quad 1<\mathrm{Br}<\mathrm{F}<\mathrm{Cl}\) increasing electron gain enthalpy (b) \(\quad \mathrm{Li}<\mathrm{Na}<\mathrm{K}<\mathrm{Rb}\) increasing metallic radius (c) \(\quad \mathrm{B}<\mathrm{C}<\mathrm{N}<\mathrm{O}\) increasing first ionization energy (d) \(\mathrm{Al}^{3+}<\mathrm{Mg}^{2+}<\mathrm{Na}^{+}<\mathrm{F}\) increasing ionic size

In which of the following arrangements, the order is not according to the property indicated against it? \([\mathbf{2 0 0 5}]\) (a) \(\quad 1<\mathrm{Br}<\mathrm{F}<\mathrm{Cl}\) increasing electron gain enthalpy (b) \(\quad \mathrm{Li}<\mathrm{Na}<\mathrm{K}<\mathrm{Rb}\) increasing metallic radius (c) \(\quad \mathrm{B}<\mathrm{C}<\mathrm{N}<\mathrm{O}\) increasing first ionization energy (d) \(\mathrm{Al}^{3+}<\mathrm{Mg}^{2+}<\mathrm{Na}^{+}<\mathrm{F}\) increasing ionic size

The increasing order of the first ionization enthalpies of the element B, P, S and F (lowest first) is (a) \(\mathrm{F}<\mathrm{S}<\mathrm{P}<\mathrm{B}\) (b) \(\mathrm{P}<\mathrm{S}<\mathrm{B}<\mathrm{F}\) (c) \(\mathrm{B}<\mathrm{P}<\mathrm{S}<\mathrm{F}\) (d) \(\mathrm{B}<\mathrm{S}<\mathrm{P}<\mathrm{F}\)