Chapter 12

The correct order of ionic radii is (a) \(\mathrm{I}^{+}>\mathrm{l}>\mathrm{I}\) (b) \(\mathrm{I}>\mathrm{I}^{+}>\mathrm{I}\) (c) \(\mathrm{I}^{+}>\mathrm{I}>\mathrm{I}^{-}\) (d) \(\mathrm{I}^{->} \mathrm{I}>\mathrm{I}^{+}\)

The first ionization energy in electron volts of nitrogen and oxygen atoms are respectively given by (a) \(14.6,13.6\) (b) \(13.6,14.6\) (c) \(13.6,13.6\) (d) \(14.6,14.6\)

The electronic configurations of some elements are given below. The element with highest electron affinity is (a) \(1 \mathrm{~s}^{2}, 2 \mathrm{~s}^{2}, 2 \mathrm{p}^{3}\) (b) \(1 \mathrm{~s}^{2}, 2 \mathrm{~s}^{2}, 2 \mathrm{p}^{4}\) (c) \(1 \mathrm{~s}^{2}, 2 \mathrm{~s}^{2}, 2 \mathrm{p}^{5}\) (d) \(1 \mathrm{~s}^{2}, 2 \mathrm{~s}^{2}, 2 \mathrm{p}^{2}\)

Arrange \(\mathrm{P}^{3-}, \mathrm{S}^{2-}, \mathrm{H}^{-}, \mathrm{I}^{-}\)in the order of increasing ionic radii (a) \(\mathrm{P}^{3-}, \mathrm{S}^{2-}, \mathrm{I}-, \mathrm{H}^{-}\) (b) \(\mathrm{S}^{2-}, \mathrm{P}^{3-}, \mathrm{H}^{-}, \mathrm{I}^{-}\) (c) \(\mathrm{S}^{2-}, \mathrm{H}^{-}, \mathrm{P}^{3-} \mathrm{I}^{-}\) (d) \(\mathrm{H}^{-}, \mathrm{S}^{2-}, \mathrm{P}^{3-}, \mathrm{I}^{-}\)

The correct value of ionisation energies (in \(\mathrm{kJ} \mathrm{mol}^{-1}\) ) of Si, P, CI and S respectively are (a) \(786,1012,999,1256\) (b) \(1012,786,999,1256\) (c) \(786,1012,1256,999\) (d) \(786,999,1012,1256\)

In which of the following process is energy librated? (a) \(\mathrm{Cl} \longrightarrow \mathrm{Cl}^{+}+\mathrm{e}\) (b) \(\mathrm{HCl} \longrightarrow \mathrm{H}^{+}+\mathrm{Cl}^{-}\) (c) \(\mathrm{Cl}+\mathrm{e} \longrightarrow \mathrm{Cl}^{-}\) (d) \(\mathrm{O}^{-}+\mathrm{e} \longrightarrow \mathrm{O}^{2-}\)

The electron affinities of \(\mathrm{N}, \mathrm{O}, \mathrm{S}\) and \(\mathrm{Cl}\) are (a) \(\mathrm{O} \approx \mathrm{Cl}<\mathrm{N} \approx \mathrm{S}\) (b) \(\mathrm{O}<\mathrm{S}<\mathrm{Cl}<\mathrm{N}\) (c) \(\mathrm{N}<\mathrm{O}<\mathrm{S}<\mathrm{Cl}\) (d) \(O<\mathrm{N}<\mathrm{Cl}<\mathrm{S}\)

While moving down a group in the periodic table, which of the following would be true? (1) all the atoms have the same number of valence electrons (2) gram atomic volume increases (3) electronegativity decreases (4) metallic character decreases and the basic nature of their oxides decreases. Select the correct answer by using the following codes: (a) 1,2 and 3 (b) 2,3 and 4 (c) 2 and 3 (d) 1 and 3

Enthalpy change in the following process is \(\mathrm{M}+\mathrm{e}^{-} \longrightarrow \mathrm{M}^{-}, \Delta \mathrm{H}=\mathrm{X} \mathrm{kJ} \mathrm{mole}^{-1}\) Which of the following process have enthalpy change \(=\mathrm{X} \mathrm{kJ} \mathrm{mole}^{-1} ?\) (a) \(\mathrm{M}^{-} \longrightarrow \mathrm{M}+\mathrm{e}^{-}\) (b) \(\mathrm{M}^{+}+\mathrm{e}^{-} \longrightarrow \mathrm{M}\) (c) \(\mathrm{M}^{2+}+\mathrm{e}^{2} \longrightarrow \mathrm{M}^{+}\) (d) \(\mathrm{M}+\mathrm{e}^{-} \longrightarrow \mathrm{M}^{-}\)

The formation of \(\mathrm{O}^{2-}(\mathrm{g})\) starting from \(\mathrm{O}(\mathrm{g})\) is endothermic by \(603 \mathrm{~kJ} \mathrm{~mol}^{-1}\). If electron affinity of \(\mathrm{O}(\mathrm{g})\) is \(-141 \mathrm{~kJ} \mathrm{~mol}^{-1}\), the second electron affinity of oxygen would be (a) \(+744 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (b) \(-744 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (c) \(+462 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (d) \(-462 \mathrm{~kJ} \mathrm{~mol}^{-1}\)

The correct order of first ionization potential is (a) \(\mathrm{F}>\mathrm{He}>\mathrm{Mg}>\mathrm{N}>\mathrm{O}\) (b) \(\mathrm{He}>\mathrm{F}>\mathrm{N}>\mathrm{O}>\mathrm{Mg}\) (c) \(\mathrm{He}>\mathrm{O}>\mathrm{F}>\mathrm{N}>\mathrm{Mg}\) (d) \(\mathrm{O}>\mathrm{F}>\mathrm{He}>\mathrm{N}>\mathrm{Mg}\)

The correct sequence of the ionic radii of the following is (a) \(\mathrm{I}>\mathrm{S}^{2-}>\mathrm{Cl}^{-}>\mathrm{O}^{2-}>\mathrm{F}^{-}\) (b) \(\mathrm{S}^{2-}>\mathrm{I}^{->}>\mathrm{O}^{2-}>\mathrm{Cl}>\mathrm{F}^{-}\) (c) \(\mathrm{I}>\mathrm{Cl}>\mathrm{S}^{2-}>\mathrm{O}^{2->} \mathrm{F}^{-}\) (d) \(\mathrm{I}^{-}>\mathrm{S}^{2}>\mathrm{Cl}^{-}>\mathrm{F}^{-}>\mathrm{O}^{2-}\)

Which of the following arrangements show the correct order of increasing lattice energy? (a) \(\mathrm{BaSO}_{4}<\mathrm{SrSO}_{4}<\mathrm{CaSO}_{4}<\mathrm{MgSO}_{4}\) (b) \(\mathrm{MgCO}_{3}<\mathrm{CaCO}_{3}<\mathrm{SrCO}_{3}<\mathrm{BaCO}_{3}\) (c) \(\mathrm{LiF}<\mathrm{LiCl}<\mathrm{LiBr}<\mathrm{Lil}\) (d) \(\mathrm{NaF}<\mathrm{KF}<\mathrm{RbF}<\mathrm{CsF}\)

The correct order of radii is (a) \(\mathrm{N}<\mathrm{Be}<\mathrm{B}\) (b) \(\mathrm{F}^{-}<\mathrm{O}^{2-}<\mathrm{N}^{3-}\) (c) \(\mathrm{Na}<\mathrm{Li}<\mathrm{K}\) (d) \(\mathrm{Fe}^{+3}<\mathrm{Fe}^{+2}<\mathrm{Fe}^{+4}\)

Which one of the following arrangements does not truly represent the property indicated against it? (a) \(\mathrm{Br}_{2}<\mathrm{Cl}_{2}<\mathrm{F}_{2}:\) electronegativity (b) \(\mathrm{Br}_{2}<\mathrm{F}_{2}<\mathrm{Cl}_{2}:\) electron affinity (c) \(\mathrm{Br}_{2}<\mathrm{Cl}_{2}<\mathrm{F}_{2}:\) bond energy (d) \(\mathrm{Br}_{2}<\mathrm{Cl}_{2}<\mathrm{F}_{2}\) : oxidizing power

The ions \(\mathrm{O}^{2}, \mathrm{~F}^{-}, \mathrm{Na}^{+}, \mathrm{Mg}^{2+}\) and \(\mathrm{Al}^{3+}\) are isoelectronic. Their ionic radii show: (a) an increase from \(\mathrm{O}^{2}\) - to \(\mathrm{F}^{-}\)and then decrease from \(\mathrm{Na}^{+}\)to \(\mathrm{Al}^{3+}\) (b) an decrease from \(\mathrm{O}^{2-}\) to \(\mathrm{F}^{-}\)and then increase from \(\mathrm{Na}^{+}\)to \(\mathrm{Al}^{3+}\) (c) a significant increase from \(\mathrm{O}^{2-}\) to \(\mathrm{Al}^{3+}\) (d) a significant decrease from \(\mathrm{O}^{2-}\) to \(\mathrm{Al}^{3+}\)

Which of the following statements are correct? (a) HF is a stronger acid than HCl. (b) among halide ions, iodide is the most powerful reducing agent. (c) fluorine is the only halogen that does not show a variable oxidation state. (d) \(\mathrm{HOCl}\) is a stronger acid than HOBr. (a) 2 and 4 (b) 2 and 3 (c) 1,2 and 3 (d) 2,3 and 4

Which one of the following orders is not in accordance with the property stated against it? (a) \(\mathrm{F}_{2}>\mathrm{Cl}_{2}>\mathrm{Br}_{2}>\mathrm{I}_{2} ;\) electronegativity (b) \(\mathrm{F}_{2}>\mathrm{Cl}_{2}>\mathrm{Br}_{2}>\mathrm{I}_{2} ;\) bond dissociation energy (c) \(\mathrm{F}_{2}>\mathrm{Cl}_{2}>\mathrm{Br}_{2}>\mathrm{I}_{2} ;\) oxidizing power (d) \(\mathrm{HI}>\mathrm{HBr}>\mathrm{HCl}>\mathrm{HF}\); acidic property in water

The electronic configuration of elements \(\mathrm{A}, \mathrm{B}\) and \(\mathrm{C}\) are \([\mathrm{He}] 2 \mathrm{~s}^{1},[\mathrm{Ne}] 3 \mathrm{~s}^{1}\) and \([\mathrm{Ar}] 4 \mathrm{~s}^{1}\) respectively. Which one of the following order is correct for the first ionization potentials (in \(\mathrm{kJ} \mathrm{mol}^{-}\)) of \(\mathrm{A}, \mathrm{B}\) and \(\mathrm{C}\) ? (a) \(\mathrm{A}>\mathrm{B}>\mathrm{C}\) (b) \(O>B>A\) (c) \(\mathrm{B}>\mathrm{O}>\mathrm{A}\) (d) \(C>A>B\)

The electronic affinity values (in \(\mathrm{kJ} \mathrm{mol}^{-1}\) ) of three halogens \(\mathrm{X}, \mathrm{Y}\) and \(\mathrm{Z}\) are respectively \(-349,-333\) and \(-325\). Then \(\mathrm{X}, \mathrm{Y}\) and \(\mathrm{Z}\) respectively are (a) \(\mathrm{F}_{2}, \mathrm{Cl}_{2}\) and \(\mathrm{Br}_{2}\) (b) \(\mathrm{Cl}_{2}, \mathrm{~F}_{2}\) and \(\mathrm{Br}_{2}\) (c) \(\mathrm{Cl}_{2}, \mathrm{Br}_{2}\) and \(\mathrm{F}_{2}\) (d) \(\mathrm{Br}_{2}^{2}, \mathrm{Cl}_{2}\) and \(\mathrm{F}_{2}\)

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

Identify the correct order in which the covalent radius of the following elements increases: (I) \(\mathrm{Ti}\) (II) \(\mathrm{Ca}\) (III) Sc (a) (I), (II), (III) (b) (II), (I), (III) (c) (I), (III), (II) (d) (III), (II), (I)

Amongst the following elements (whose electronic configurations are given below), the correct increasing order of ionization energy is (1) \([\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{1}\) (2) \([\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{3}\) (3) \([\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{2}\) (4) \([\mathrm{Ar}] 3 \mathrm{~d}^{10} 4 \mathrm{~s}^{2} 4 \mathrm{p}^{3}\) (a) \(3<\mathrm{k}<2<4\) (b) \(4<2<3<1\) (c) \(\mathrm{k}<3<4<2\) (d) \(2<4<1<3\)

Identify the correct order of acidic strengths of \(\mathrm{CO}_{2}\), \(\mathrm{CuO}, \mathrm{CaO}\) and \(\mathrm{H}_{2} \mathrm{O} .\) (a) \(\mathrm{CaO}<\mathrm{CuO}<\mathrm{H}_{2} \mathrm{O}<\mathrm{CO}_{2}\) (b) \(\mathrm{H}_{2} \mathrm{O}<\mathrm{CuO}<\mathrm{CaO}<\mathrm{CO}_{2}^{2}\) (c) \(\mathrm{CaO}<\mathrm{H}_{2} \mathrm{O}<\mathrm{CuO}<\mathrm{CO}_{2}\) (d) \(\mathrm{H}_{2} \mathrm{O}<\mathrm{CO}_{2}<\mathrm{CaO}<\mathrm{CuO}\)

The correct statement among the following is (a) the first ionization potential of \(\mathrm{Al}\) is less than the first ionization potential of \(\mathrm{Mg}\). (b) the second ionization potential of \(\mathrm{Mg}\) is greater than the second ionization potential of \(\mathrm{Na}\). (c) the first ionization potential of \(\mathrm{Na}\) is less than the first ioniation potential of \(\mathrm{Mg}\). (d) the third ionization potential of \(\mathrm{Mg}\) is greater than the third ionization potential of Al.

The statement that is not correct for periodic classification of elements is (a) the properties of elements are a periodic function of their atomic numbers. (b) non-metallic elements are less in number than metallic elements. (c) the first ionization energies of elements along a period do not vary in a regular manner with in crease in atomic number. (d) for transition elements, the d-subshells are filled with electrons monotonically with increase in atomic number.

The first ionization potential of \(\mathrm{Na}, \mathrm{Mg}, \mathrm{Al}\) and \(\mathrm{Si}\) are in the order: (a) \(\mathrm{Na}>\mathrm{Mg}>\mathrm{Al}<\mathrm{Si}\) (b) \(\mathrm{Na}>\mathrm{Mg}>\mathrm{Al}>\mathrm{Si}\) (c) \(\mathrm{Na}<\mathrm{Mg}<\mathrm{Al}<\mathrm{Si}\) (d) \(\mathrm{Na}<\mathrm{Mg}>\mathrm{Al}>\mathrm{Si}\)

The electronegativity of the following elements increases in the order: (a) \(\mathrm{Si}, \mathrm{P}, \mathrm{C}, \mathrm{N}\) (b) \(\mathrm{N}, \mathrm{Si}, \mathrm{C}, \mathrm{P}\) (c) \(\mathrm{P}, \mathrm{Si}, \mathrm{N}, \mathrm{C}\) (d) \(\mathrm{C}, \mathrm{N}, \mathrm{Si}, \mathrm{P}\)

Atomic radii of fluorine and neon in Angstorm units are given respectively by (a) \(1.60,1.60\) (b) \(0.72,0.72\) (c) \(0.72,1.60\) (d) none of these

The element with the highest first ionization potential is (a) nitrogen (b) oxygen (c) boron (d) carbon

The correct order of second ionization potential of carbon, nitrogen, oxygen and fluorine is (a) \(\mathrm{O}>\mathrm{N}>\mathrm{F}>\mathrm{C}\) (b) \(\mathrm{O}>\mathrm{F}>\mathrm{N}>\mathrm{C}\) (c) \(\mathrm{F}>\mathrm{O}>\mathrm{N}>\mathrm{C}\) (d) \(C>N>O>F\)

The correct increasing bond angle among \(\mathrm{BF}_{3}, \mathrm{PF}_{3}\) and \(\mathrm{C} 1 \mathrm{~F}_{3}\) follows the order (a) \(\mathrm{BF}_{3}<\mathrm{PF}_{3}<\mathrm{CIF}_{3}\) (b) \(\mathrm{PF}_{3}<\mathrm{BF}_{3}<\mathrm{CIF}_{3}\) (c) \(\mathrm{CIF}_{3}<\mathrm{PF}_{3}<\mathrm{BF}_{3}\) (d) \(\mathrm{BF}_{3}<\mathrm{PF}_{3}<\mathrm{CIF}_{3}\)

Which ionization potential in the following equations involves the greatest amount of energy? (a) \(\mathrm{Na} \longrightarrow \mathrm{Na}^{+}+\mathrm{e}^{-}\) (b) \(\mathrm{K} \longrightarrow \mathrm{K}^{+} \mathrm{e}^{-}\) (c) \(\mathrm{Cs}^{2+} \longrightarrow \mathrm{Cs}^{3+}+\mathrm{e}^{-}\) (d) \(\mathrm{Ca}^{+} \longrightarrow \mathrm{Ca}^{2+}+\mathrm{e}^{-}\)

Among the elements \(\mathrm{W}, \mathrm{X}, \mathrm{Y}\) and \(\mathrm{Z}\) having atomic numbers \(9,10,11\) and 12 respectively, the correct order of ionization energies is (a) \(\mathrm{W}>\mathrm{Y}>\mathrm{X}>\mathrm{Z}\) (b) \(\mathrm{X}>\mathrm{W}>\mathrm{Z}>\mathrm{Y}\) (c) \(X>Z>Y>W\) (d) \(\mathrm{Z}>\mathrm{Y}>\mathrm{X}>\mathrm{W}\)

Which of the following orders are correct? (i) Thermal stability \(\mathrm{BeCO}_{3}<\mathrm{MgCO}_{3}<\mathrm{CaCO}_{3}<\mathrm{SrCO}_{3}<\mathrm{BaCO}_{3}\) (ii) Basic nature \(\mathrm{LiOH}>\mathrm{NaOH}>\mathrm{KOH}>\mathrm{RbOH}>\mathrm{CsOH}\) (iii) Solubility in water \(\mathrm{BeSO}_{4}<\mathrm{MgSO}_{4}<\mathrm{CaSO}_{4}<\mathrm{SrSO}_{4}<\mathrm{BaSO}_{4}\) (iv) Melting point \(\mathrm{NaCl}>\mathrm{KCl}>\mathrm{RbCI}>\mathrm{CsCl}>\mathrm{LiCl}\) (a) (i), (iv) (b) (i), (ii), (iv) (c) (ii), (iii) (d) (i), (ii) (iii), (iv)

Match the following: List 1 List II 1\. \(\mathrm{Li}<\mathrm{Na}<\mathrm{K}<\mathrm{R} \mathrm{b}\) (i) increasing order energy 2\. \(\mathrm{Li}<\mathrm{Be}>\mathrm{B}<\mathrm{C}\) (ii) decreasing order of metallic nature 3\. \(\mathrm{F}_{2}>\mathrm{Cl}_{2}>\mathrm{Br}_{2}>\mathrm{I}_{2}\) (iii) increasing order of size 4\. \(\mathrm{F}_{2}>\mathrm{O}_{2}>\mathrm{Cl}_{2}>\mathrm{s}\) (iv) increasing order of electron affinity The correct matching is: 1 2 3 4 (a) (i) (iv) (ii) (iii) (b) (iii) (i) (iv) (ii) (c) (iii) (i) (ii) (iv) (d) (i) (ii) (iii) (iv)

Match the following: List I List II 1\. element with highest (i) \(\mathrm{I}_{2}\) electronegativity 2\. element with highest (ii) \(\mathrm{Br}_{2}\) electron affinity 3\. liquid non metal (iii) \(\mathrm{Cl}_{2}\) 4\. metallic solid (iv) \(\mathrm{F}_{2}\) The correct matching is: (1) (2) (3) (4) (a) (iii) (ii) (i) (iv) (b) (iv) (iii) (i) (ii) (c) (ii) (iii) (iv) (i) (d) (i) (ii) (iii) (iv)

Calculate the electronegativity of fluorine from the following data. \(\mathrm{E}_{\mathrm{H}-\mathrm{H}}=104.2 \mathrm{Kcal} \mathrm{mol}^{-1}\) \(\mathrm{E}_{\mathrm{F}-\mathrm{F}}=36.6 \mathrm{Kcal} \mathrm{mol}^{-1}\) \(\mathrm{E}_{\mathrm{H}-\mathrm{F}}=134.6 \mathrm{Kcal} \mathrm{mol}^{-1}\) \(\mathrm{X}_{\mathrm{H}}=2.1\) (a) \(2.86\) (b) \(3.76\) (c) \(1.86\) (d) \(3.26\)

For the gaseous reaction, \(\mathrm{K}+\mathrm{F} \longrightarrow \mathrm{K}^{+}+\mathrm{F}^{-}, \Delta \mathrm{H}\) was calculated to be \(19 \mathrm{kcal}\) under conditions where the cations and anions were prevented by electrostatic separation from combining with each other. The ionization potential of \(\mathrm{K}\) is \(4.3 \mathrm{eV}\). What is the electron affinity of \(\mathrm{F}\) ? (a) \(3.21\) (b) \(4.28\) (c) \(3.48\) (d) \(1.48\)

The successive ionization energy values for an element \(\mathrm{X}\) are given below: (a) 1st ionization energy \(=410 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (b) 2 nd ionization energy \(=820 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (c) 3 rd ionization energy \(=1100 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (d) 4 th ionization energy \(=1500 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (e) 5 th ionization energy \(=3200 \mathrm{~kJ} \mathrm{~mol}^{-1}\) Find out the number of valence electron for the atom, \(\mathrm{X}\) (a) 4 (b) 3 (c) 5 (d) 2

The electronic configuration of four elements are (i) \([\mathrm{Xe}] 6 \mathrm{~s}^{1}\) (ii) \([\mathrm{Xe}] 4 \mathrm{f}^{14} 5 \mathrm{~d}^{1} 6 \mathrm{~s}^{2}\) (iii) \([\mathrm{Ar}] 4 \mathrm{~s}^{2} 4 \mathrm{p}^{5}\) (iv) \([\mathrm{Ar}] 3 \mathrm{~d}^{7} 4 \mathrm{~s}^{2}\) Which one of the following statements about these elements is not correct? (a) (i) is a strong reducing agent (b) (ii) is a d block element (c) (iii) has high electron affinity (d) (iv) shows variable oxidation state

Which of the following statements is/are not true about the diagonal relationship of Be and Al? (1) Both react with \(\mathrm{NaOH}\) to liberate hydrogen (2) Their oxides are basic (3) They are made passive by nitric acid (4) Their carbides give acetylene on treatment with water (a) only (1) (b) (2) and (3) (c) only (4) (d) (2) and (4)

Pick out the statement(s) which is are not true about the diagonal relationship of \(\mathrm{Li}\) and \(\mathrm{Mg}\). (1) Polarizing powers of \(\mathrm{Li}^{+}\)and \(\mathrm{Mg}^{2+}\) are almost same. (2) Like Li, Mg decomposes water very fast. (3) \(\mathrm{LiCl}\) and \(\mathrm{MgCl}_{2}\) are deliquescent. (4) Like \(\mathrm{Li}, \mathrm{Mg}\) readily reacts with liquid bromine at ordinary temperature. (a) (1) and (4) (b) (2) and (4) (c) only (2) (d) only(l)

The correct statement among the following is (a) the first ionization potential of \(\mathrm{Al}\) is less than the first ionization potential of \(\mathrm{Mg}\) (b) the second ionization potential of \(\mathrm{Mg}\) is greater than the second ionization potential of Na (c) the first ionization potential of \(\mathrm{Na}\) is less than the first ioniation potential of \(\mathrm{Mg}\) (d) the third ionization potential of \(\mathrm{Mg}\) is greater than the third ionization potential of \(\mathrm{Al}\)

The statement that is not correct for periodic classification of elements is (a) the properties of elements are a periodic function of their atomic numbers (b) non-metallic elements are less in number than metallic elements (c) the first ionization energies of elements along a period do not vary in a regular manner with in crease in atomic number (d) for transition elements, the d-subshells are filled with electrons monotonically with increase in atomic number

Which of the following statement (s) is /are true? (a) ionization energy \(\alpha \frac{1}{\text { Screening effect }}\) (b) The first ionization energies of Be and \(\mathrm{Mg}\) are more than ionization energies of \(\mathrm{B}\) and \(\mathrm{Al}\) respectively (c) Atomic and ionic radii of Niobium and Tantalum are almost same (d) Metallic and covalent radii of potassium are \(2.3 \mathrm{~A}\) and \(2.03 \AA\) respectively

Which of the following statement (s) is/are true for IA elements? (a) Na is regarded as a typical representative element. (b) Basic character of their oxides increases down the group. (c) Among alkali metal ions degree of hydration is the highest in Li. (d) In general electron affinity values decrease from top to bottom in the group.

Which of the following statements is/are correct? (a) Successive ionization energies of an atom always increase. (b) The electron affinity for sulphur is more exothermic than that for oxygen. (c) First ionization enegy of As is greater than that of Se. (d) Chlorine has larger atomic size as well as electron affinity than that of fluorine.

Which of the following pair (s) represent (s) the isoelectronic species? (a) \(\mathrm{S}^{2-} \& \mathrm{Sc}^{3+}\) (b) \(\mathrm{SO}_{2} \& \mathrm{NO}_{3}^{-}\) (c) \(\mathrm{N}_{2} \& \mathrm{CN}\) (d) \(\mathrm{NH}_{3} \& \mathrm{H}_{3} \mathrm{O}^{+}\)

Which of the following represent (s) the correct order of electron affinities? (a) \(\mathrm{F}>\mathrm{Cl}>\mathrm{Br}>\mathrm{I}\) (b) \(\mathrm{C}<\mathrm{N}<\mathrm{Cl}<\mathrm{F}\) (c) \(\mathrm{N}<\mathrm{C}<\mathrm{O}<\mathrm{F}\) (d) \(\mathrm{C}<\mathrm{Si}>\mathrm{P}>\mathrm{N}\)