Problem 109
The MO clectron configuration of peroxide ion \(\left(O_{2}^{2}\right)\) is (1) \(\mathrm{KK}^{*}\left[\sigma 2 \mathrm{~s}^{2} \sigma^{*} 2 \mathrm{~s}^{2} \sigma 2 \mathrm{p}_{x}^{2} \pi 2 \mathrm{p}_{x}^{2} \pi 2 \mathrm{p}_{\mathrm{y}}^{2} \pi * 2 \mathrm{p}_{x}^{2} \pi+2 \mathrm{p}_{\mathrm{y}}^{2}\right]\) (2) \(\mathrm{KK}^{*} \mid \sigma 2 \mathrm{~s}^{2} \sigma^{*} 2 \mathrm{~s}^{2} \sigma 2 \mathrm{p}_{z}^{2} \pi 2 \mathrm{p}_{\mathrm{x}}^{2} \pi 2 \mathrm{p}_{\mathrm{y}}^{2} \pi^{*} 2 \mathrm{p}_{\mathrm{x}}^{1} \pi^{*} 2 \mathrm{p}_{\mathrm{y}}^{1} \mathrm{l}\) (3) \(\mathrm{KK}^{*}\left[\sigma 2 \mathrm{~s}^{2} \sigma^{*} 2 \mathrm{~s}^{2} \sigma 2 \mathrm{p}_{z}^{2} \pi 2 \mathrm{p}_{\mathrm{x}}^{2} \pi 2 \mathrm{p}_{y}^{2} \pi^{*} 2 \mathrm{p}_{\mathrm{x}}^{2} \pi^{*} 2 \mathrm{p}_{y}^{\prime}\right]\) (4) \(\mathrm{KK}^{*} \mid \sigma 2 \mathrm{~s}^{2} \sigma^{*} 2 \mathrm{~s}^{2} \sigma 2 \mathrm{p}_{k}^{2} \pi 2 \mathrm{p}_{x}^{2} \pi 2 \mathrm{p}_{y}^{2} \pi * 2 \mathrm{p}_{\mathrm{x}}^{2} \mathrm{l}\)
Problem 111
A molecular orbital in a polyatomic molecule is (1) monocentric (2) bicentric (3) polycentric (4) none of these
Problem 112
Which of the following sets are isoelectronic? (1) \(\mathrm{N}_{2}, \mathrm{O}_{2}^{2}\) (2) \(\mathrm{N}_{2}, \mathrm{O}_{2}^{21}\) (3) \(\mathrm{N}_{2}^{-}, \mathrm{O}_{2}^{-}\) (4) \(\mathrm{N}_{2}, \mathrm{O}_{2}^{-}\)
Problem 114
Which statement of the following is false for isoelectronic species? (1) They have same outer electronic configuration. (2) Their bond orders are same. (3) Their outer electronic configuration is different. (4) Their bond energies are nearly same.
Problem 115
In the conversion of \(\mathrm{N}_{2}\) to \(\mathrm{N}_{2}^{+}\) ion the electron is removed from (1) \(\sigma\) orbital (2) \(\sigma^{*}\) orbital (3) \(\pi\) orbital (4) \(\pi^{*}\) orbital
Problem 116
In the conversion of \(\mathrm{O}_{2}\) to superoxide ion, the electron is added to (1) \(\sigma\) -orbital (2) \(\sigma^{*}\) -orbital (3) \(\pi\) -orbital (4) \(\pi^{*}\) -orbital
Problem 117
In an anti-bonding MO the clectron density is minimum (1) around one atom of the molecule (2) between the nuclei (3) at a point away from nuclci of the molecule (4) at no place
Problem 118
The paramagnetism of \(\mathrm{O}_{2}\) molecule is believed to be due to the presence of two electrons in (1) bonding \(\pi\) -orbitals with parallel spin (2) antibonding \(\pi\) -orbitals with parallcl spin (3) antibonding \(\pi\) -orbitals with opposite spin (4) antibonding o-orbitals with parallel spin
Problem 122
Which of the following statements is correct? (1) If bond order is zero or negative the molecule formed is unstable. (2) If bond order is positive, the bond formed is stable. (3) Bond dissociation energy is directly proportional to the bond order. (4) All arc correct.
Problem 127
Which of the following statements is not correct regarding bonding MOs? (1) Bonding MOs possess less energy than the atomic orbitals from which they are formed. (2) Bonding MOs have low electron densities between the nuclei. (3) Every electron in bonding MO contributes to the attraction between atoms. (4) They are formed when the lobes of the combining atomic orbitals overlap.
