Define molecular orbitals.

Important Questions on Chemical Bonding and Molecular Structure

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

After understanding the assertion and reason, choose the correct option.

Assertion: In the bonding molecular orbital (MO) of ${\text{H}}_2,$ electron density is increased between the nuclei.
Reason: The bonding MO is ${\mathrm{\text{ψ}}}_{\mathrm{\text{A}}}+{\mathrm{\text{ψ}}}_{\mathrm{\text{B}}}$ , which shows destructive interference of the combining electron waves.

HARD

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Decreasing order of stability of ${\mathrm{O}}_2,\mathrm{ }{\mathrm{O}}_2^{-},\mathrm{ }{\mathrm{O}}_2^{+}$ and ${\mathrm{O}}_2^{2-}$ is:

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which of the following species is not paramagnetic?

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which of the following is paramagnetic?

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Stability of the species  ${\text{Li}}_2\text{,}{\text{Li}}_2^{-}\text{and}{\text{Li}}_2^{+}$ increases in the order of

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Consider the following species:

(i) $O_2^{2-}$

(ii) $C{O}^{+}$

(iii) $O_2^{+}$

Among the following, sigma bond alone is present in -

HARD

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which of the following options represents the correct bond order?

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which one of the following molecules is paramagnetic?

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

In which of the following pairs of molecules/ions, both the species are not likely to exist?

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which one of the following molecules is expected to exhibit paramagnetic behaviour?

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which one of the following pairs of species has the same bond order?

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Two pi and half sigma bonds are present in:

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which one of the following properties is not shown by NO ?

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

The diamagnetic species is:

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Which of the following has unpaired electron(s)?

HARD

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

Assuming $2\mathrm{s}\mathrm{ }–\mathrm{ }2\mathrm{p}$ mixing is NOT operative, the paramagnetic species among the following is

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

According to molecular orbital theory, which of the following molecule will not be available?

MEDIUM

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

The correct bond order in the following species is:

HARD

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

In which of the following processes, the bond order has increased and paramagnetic character has changed to diamagnetic?

EASY

Chemistry>Inorganic Chemistry>Chemical Bonding and Molecular Structure>Molecular Orbital Theory (MOT)

According to molecular orbital theory, which of the following is true with respect to ${\mathrm{Li}}_2^{+}$ and ${\mathrm{Li}}_2^{-}$ ?