Among $KO_2$, $AlO_2^-$ , $BaO_2$ and $NO_2^+$, unpaired electron is present in
- $NO_2^+$ and $BaO_2$
- $KO_2$, and $AlO_2^-$
- Only $KO_2$
- Only $BaO_2$
The Correct Option is C
Solution and Explanation
The correct option is(C): KO2.
Number of electrons has to be calculated:
NO2+: 5+6(2)-1 =16 electrons
AlO2- = 3+6(2) +1 = 16 electrons
BaO2 = 2+6(2)= 14 electrons
KO2 =1 +6(2) = 13 electrons
All the compounds have paired electrons except KO2. Therefore, the answer is KO2
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Molecular Orbital Theory
The Molecular Orbital Theory is a more sophisticated model of chemical bonding where new molecular orbitals are generated using a mathematical process called Linear Combination of Atomic Orbitals (LCAO).
Molecular Orbital theory is a chemical bonding theory that states that individual atoms combine together to form molecular orbitals. Due to this arrangement in MOT Theory, electrons associated with different nuclei can be found in different atomic orbitals. In molecular orbital theory, the electrons present in a molecule are not assigned to individual chemical bonds between the atoms. Rather, they are treated as moving under the influence of the atomic nuclei in the entire molecule.
