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) \(\mathrm{Ar} \rightarrow \mathrm{Ar}\)

Properties that are directly or indirectly related to the electronic configuration of the elements and show a regular gradation when we move from left to right in a period or form top to bottom in a group are called periodic properties. Some of these properties are ionization energy, electron affinity and electronegativity 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) \(\mathrm{B}<\mathrm{C}<\mathrm{N}<\mathrm{O}<\mathrm{F}<\mathrm{Be}<\mathrm{Ne}\)

Properties that are directly or indirectly related to the electronic configuration of the elements and show a regular gradation when we move from left to right in a period or form top to bottom in a group are called periodic properties. Some of these properties are ionization energy, electron affinity and electronegativity 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) \(\mathrm{Cl}>\mathrm{F}>\mathrm{Br}>\mathrm{S}>\mathrm{Si}>\mathrm{I}\)

Properties that are directly or indirectly related to the electronic configuration of the elements and show a regular gradation when we move from left to right in a period or form top to bottom in a group are called periodic properties. Some of these properties are ionization energy, electron affinity and electronegativity 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) \(\mathrm{Cu}, \mathrm{Fe}, \mathrm{Mg}\)

According to Modern Periodic Law, the physical and chemical properties of elements are a periodic function of their atomic number. When the elements are arranged according to this law, a table is obtained in which the elements with similar properties are placed together. The properties of elements are gradually changing but repeated at regular intervals. An element has exceptional outer electronic configuration as \(4 \mathrm{~d}^{10} 5 \mathrm{~s}^{0}\). It belongs to (a) 5 th period, group 10 (b) 4 th period, group 11 (c) 5 th period, group 11 (d) 4th period, group 10

According to Modern Periodic Law, the physical and chemical properties of elements are a periodic function of their atomic number. When the elements are arranged according to this law, a table is obtained in which the elements with similar properties are placed together. The properties of elements are gradually changing but repeated at regular intervals. The correct order of atomic size of \(\mathrm{C}, \mathrm{N}, \mathrm{P}\) and \(\mathrm{S}\) follows the order (a) \(C

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

In the following questions two statements (Assertion) (A) and Reason (R) are given. Mark (a) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct and \(\mathrm{R}\) is the correct explanation of \(\mathrm{A}\). (b) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct but \(\mathrm{R}\) is not the correct expalnation of \(\mathrm{A}\). (c) A is true but \(\mathrm{R}\) is false. (d) A is false but \(R\) is true. (e) \(\mathrm{A}\) and \(\mathrm{R}\) both are false. Assertion: Fluorine forms only one oxoacid, HOF because. Reason: Fluorine has small size and high electronegativity.

In the following questions two statements (Assertion) (A) and Reason (R) are given. Mark (a) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct and \(\mathrm{R}\) is the correct explanation of \(\mathrm{A}\). (b) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct but \(\mathrm{R}\) is not the correct expalnation of \(\mathrm{A}\). (c) A is true but \(\mathrm{R}\) is false. (d) A is false but \(R\) is true. (e) \(\mathrm{A}\) and \(\mathrm{R}\) both are false. Assertion: Lithium slats are mostly hydrated amongst alkalimetal salts Reason: The hydration enthalpies of alkali metal ions increases with decrease in ionic sizes

In the following questions two statements (Assertion) (A) and Reason (R) are given. Mark (a) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct and \(\mathrm{R}\) is the correct explanation of \(\mathrm{A}\). (b) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct but \(\mathrm{R}\) is not the correct expalnation of \(\mathrm{A}\). (c) A is true but \(\mathrm{R}\) is false. (d) A is false but \(R\) is true. (e) \(\mathrm{A}\) and \(\mathrm{R}\) both are false. Assertion: The 5 th period of periodic table contains 18 elements not 32 . Reason: \(\mathrm{n}=5,1=0,1,2,3\). The order in which the energy of available orbitals \(4 \mathrm{~d}, 5 \mathrm{~s}\) and \(5 \mathrm{p}\)

In the following questions two statements (Assertion) (A) and Reason (R) are given. Mark (a) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct and \(\mathrm{R}\) is the correct explanation of \(\mathrm{A}\). (b) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct but \(\mathrm{R}\) is not the correct expalnation of \(\mathrm{A}\). (c) A is true but \(\mathrm{R}\) is false. (d) A is false but \(R\) is true. (e) \(\mathrm{A}\) and \(\mathrm{R}\) both are false. Assertion: The \(4 \mathrm{f}\) and \(5 \mathrm{f}\) - 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.

In the following questions two statements (Assertion) (A) and Reason (R) are given. Mark (a) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct and \(\mathrm{R}\) is the correct explanation of \(\mathrm{A}\). (b) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct but \(\mathrm{R}\) is not the correct expalnation of \(\mathrm{A}\). (c) A is true but \(\mathrm{R}\) is false. (d) A is false but \(R\) is true. (e) \(\mathrm{A}\) and \(\mathrm{R}\) both are false. Assertion: The first ionization energy of Be is greater than that of \(\mathrm{B}\). Reason: \(2 \mathrm{p}\) orbital is lower in energy than \(2 \mathrm{~s}\). 131 .

In the following questions two statements (Assertion) (A) and Reason (R) are given. Mark (a) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct and \(\mathrm{R}\) is the correct explanation of \(\mathrm{A}\). (b) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct but \(\mathrm{R}\) is not the correct expalnation of \(\mathrm{A}\). (c) A is true but \(\mathrm{R}\) is false. (d) A is false but \(R\) is true. (e) \(\mathrm{A}\) and \(\mathrm{R}\) both are false. Assertion: Third ionization energy of phosphorus is larger than sulphur. Reason: There is a larger amount of stability associated with filled s- and p-sub-shells (a noble gas electron configuration) which corresponds to having eight electrons in the valence shell of an atom or iron.

In the following questions two statements (Assertion) (A) and Reason (R) are given. Mark (a) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct and \(\mathrm{R}\) is the correct explanation of \(\mathrm{A}\). (b) If both \(\mathrm{A}\) and \(\mathrm{R}\) are correct but \(\mathrm{R}\) is not the correct expalnation of \(\mathrm{A}\). (c) A is true but \(\mathrm{R}\) is false. (d) A is false but \(R\) is true. (e) \(\mathrm{A}\) and \(\mathrm{R}\) both are false. 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?

The values of \(\mathrm{IE}_{1}, \mathrm{IE}_{2}, \mathrm{IE}_{3}, \mathrm{IE}_{4}\) and \(\mathrm{IE}_{5}\) are \(7.1,14.3\), \(34.5,46.8\) and \(162.2 \mathrm{eV}\) respectively. Number of valence electrons in that element is

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

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

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 one of the following groupings represents a collection of isoelectronic species? (At. number of Cs \(=55, \mathrm{Br}=35\) ) \(\quad\) [2003] (a) \(\mathrm{Na}^{+}, \mathrm{Ca}^{2+}, \mathrm{Mg}^{2+}\) (b) \(\mathrm{N}^{3-}, \mathrm{F}^{-}, \mathrm{Na}^{+}\) (c) \(\mathrm{Be}, \mathrm{Al}^{3+}, \mathrm{F}^{-}\) (d) \(\mathrm{Ca}^{2+}, \mathrm{Cs}^{+}, \mathrm{Br}\)

Which one of the following is an amphoteric oxide? \([\mathbf{2 0 0 3}]\) (a) \(\mathrm{ZnO}\) (b) \(\mathrm{Na}_{2} \mathrm{O}\) (c) \(\mathrm{SO}_{2}\) (d) \(\mathrm{B}_{2} \mathrm{O}_{2}\)

Which one the following sets of ions represents the collection of isoelectronic species? (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) \(\mathrm{Na}^{+}, \mathrm{Mg}^{2+}, \mathrm{Al}^{3+}, \mathrm{Cl}-\)

Among \(\mathrm{A} 1_{2} \mathrm{O}_{3}, \mathrm{SiO}_{2}, \mathrm{P}_{2} \mathrm{O}_{3}\) and \(\mathrm{SO}_{2}\) the correct order of acidic strength is (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) \(\mathrm{Al}, \mathrm{O}_{3}<\mathrm{SiO},<\mathrm{SO},<\mathrm{P}_{3} \mathrm{O}\)

The formation of the oxide ion \(\mathrm{O}^{2-}(\mathrm{g})\) require first an exothermic and then an endothermic step as shown below \(\mathrm{O}(\mathrm{g})+\mathrm{e}^{-} \longrightarrow \mathrm{O}^{-}(\mathrm{g}) ; \Delta \mathrm{H}^{0}=-142 \mathrm{~kJ} \mathrm{~mol}^{-1}\) \(\mathrm{O}^{-}(\mathrm{g})+\mathrm{e}^{-} \longrightarrow \mathrm{O}^{2-}(\mathrm{g}) ; \Delta \mathrm{H}^{0}=844 \mathrm{~kJ} \mathrm{~mol}^{-1}\) 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

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 \([\mathbf{2 0 0 5}]\) (a) \(\mathrm{Zr}\), Hf have about the same radius (b) \(\mathrm{Zr}, \mathrm{Y}\) have about the same radius (c) \(\mathrm{Zr}\), Nb have same oxidation state (d) \(\mathrm{Zr}, \mathrm{Zn}\) have same oxidation state

In which of the following arrangements, the order is not according to the property indicated against it? \([2005]\) (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 B

Which one of the following sets of ions represents a collection of isoelectronic species? [2006] (a) \(\mathrm{K}^{+}, \mathrm{Cl}^{-}, \mathrm{Ca}^{2+}, \mathrm{Sc}^{3+}\) (b) \(\mathrm{Ba}^{2+}, \mathrm{Sr}^{2+}, \mathrm{K}^{+}, \mathrm{Ca}^{2+}\) (c) \(\mathrm{N}^{3}, \mathrm{O}^{2-}, \mathrm{F}^{-}, \mathrm{S}^{2-}\) (d) \(\mathrm{Li}^{+}, \mathrm{Na}^{+}, \mathrm{Mg}^{2+}, \mathrm{Ca}^{2+}\)

The increasing order of the first ionization enthalpies of the element \(\mathrm{B}, \mathrm{P}, \mathrm{S}\) and \(\mathrm{F}\) (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) \(\mathrm{B}<\mathrm{S}<\mathrm{P}<\mathrm{F}\)

The set representing the correct order of ionic radius is: (a) \(\mathrm{Na}^{+}>\mathrm{Li}^{+}>\mathrm{Mg}^{2+}>\mathrm{Be}^{2+}\) (b) \(\mathrm{Li}^{+}>\mathrm{Na}^{+}>\mathrm{Mg}^{2+}>\mathrm{Be}^{2+}\) (c) \(\mathrm{Mg}^{2+}>\mathrm{Be}^{2+}>\mathrm{Li}^{2+}>\mathrm{Na}^{+}\) (d) \(\mathrm{Li}^{+}>\mathrm{Be}^{2+}>\mathrm{Na}^{+}>\mathrm{Mg}^{2+}\)

The correct sequence which shows decreasing order of the ionic radii of the elements is (a) \(\mathrm{Al}^{3+}>\mathrm{Mg}^{2+}>\mathrm{Na}^{+}>\mathrm{F}^{-}>\mathrm{O}^{2-}\) (b) \(\mathrm{Na}^{+}>\mathrm{Mg}^{2+}>\mathrm{Al}^{3+}>\mathrm{O}^{2-}>\mathrm{F}^{-}\) (c) \(\mathrm{Na}^{+}>\mathrm{F}^{-}>\mathrm{Mg}^{2+}>\mathrm{O}^{2-}>\mathrm{Al}^{3+}\) (d) \(\mathrm{O}^{2-}>\mathrm{F}^{-}>\mathrm{Na}^{+}>\mathrm{Mg}^{2+}>\mathrm{Al}^{3+}\)

The increasing order of the ionic radii of the given isoelectronic species is: (a) \(\mathrm{Ca}^{2+}, \mathrm{K}^{+}, \mathrm{Cl}^{-}, \mathrm{S}^{2-}\) (b) \(\mathrm{S}^{2}, \mathrm{Cl}^{-}, \mathrm{Ca}^{2+}, \mathrm{K}^{+}\) (c) \(\mathrm{Cl}^{-}, \mathrm{Ca}^{2+}, \mathrm{K}^{+}, \mathrm{S}^{2-}\) (d) \(\mathrm{K}^{+}, \mathrm{S}^{2-}, \mathrm{Ca}^{2+}, \mathrm{Cl}\)

The first ionisation potential of \(\mathrm{Na}\) is \(5.1 \mathrm{ev}\). The value of electron gain enthalpy of \(\mathrm{Na}^{+}\)will be? (a) \(-2.55 \mathrm{ev}\) (b) \(-5.1 \mathrm{ev}\) (c) \(-10.2 \mathrm{ev}\) (d) \(2.25 \mathrm{ev}\)

Which of the following arrangement represents the increasing order of Ionic radii of the given species \(0^{-2}\), \(\mathrm{S}^{-2}, \mathrm{~N}^{-3}, \mathrm{P}^{-3}\) (a) \(\mathrm{S}^{-2}<\mathrm{P}^{-3}<\mathrm{N}^{-3}<0^{-2}\) (b) \(0^{-2}<\mathrm{N}^{-3}<\mathrm{S}^{-2}<\mathrm{P}^{-3}\) (c) \(0^{-2}<\mathrm{P}^{3-}<\mathrm{N}^{3-}<\mathrm{S}^{-2}\) (d) \(\mathrm{N}^{-3}<\mathrm{S}^{-2}<0^{-2}<\mathrm{P}^{-3}\)

The Ionic radii (in \(\mathrm{A}\) ) of \(\mathrm{N}^{-3}, \mathrm{O}^{-2}, \mathrm{~F}^{-}\)are respectively? [2015] (a) \(1.36,1.4\) and \(1.71\) (b) \(1.36,1.71\) and \(1.4\) (c) \(1.71,1.4\) and \(1.36\) (d) \(1.71,1.36\) and \(1.4\)