List of top Chemistry Questions on Molecular Orbital Theory

Which of the following statement is true with respect to H$_2$O, NH$_3$ and CH$_4$?
(A) The central atoms of all the molecules are sp$^3$ hybridized.
(B) The H–O–H, H–N–H and H–C–H angles in the above molecules are 104.5°, 107.5° and 109.5° respectively.
(C) The increasing order of dipole moment is CH$_4$<NH$_3$<H$_2$O.
(D) Both H$_2$O and NH$_3$ are Lewis acids and CH$_4$ is a Lewis base.
(E) A solution of NH$_3$ in H$_2$O is basic. In this solution NH$_3$ and H$_2$O act as Lowry-Bronsted acid and base respectively.

The sum of the bond orders of O$_2^+$, O$_2^-$, O$_2$, O$_2^{2-$, and the sum of the unpaired electrons in them respectively are

Regarding the molecular orbital (MO) energy levels for homonuclear diatomic molecules, the INCORRECT statement(s) is (are):

Energy of H atom in ground state is 13.6 eV. No of spectral lines emitted by 'H' atom when a photon of energy 12.75 eV is received?

In the following, the number of paramagnetic molecules are: O$_2$, N$_2$, F$_2$, B$_2$, Cl$_2$.

Which of the following is the ratio of 5$^\text{th}$ Bohr orbit $ (r_5) $ of He$^+$ & Li$^{2+}$?

Which of the following linear combinations of atomic orbitals will lead to the formation of molecular orbitals in homonuclear diatomic molecules (internuclear axis in z-direction)?
(1) $ 2p_z $ and $ 2p_x $
(2) $ 2s $ and $ 2p_x $
(3) $ 3d_{xy} $ and $ 3d_{x^2-y^2} $
(4) $ 2s $ and $ 2p_z $
(5) $ 2p_z $ and $ 3d_{x^2-y^2} $

Total number of electrons present in $ (\pi^*) $ molecular orbitals of $ \text{O}_2 $, $ \text{O}_2^+ $, and $ \text{O}_2^- $ is __________ .

Given below are two statements:
Statement I: Diamagnetic $li_2$ molecules are known to exist in the vapour phase.
Statement II: According to MO theory, double bond in $C_2$ consists of both $ \pi $ bonds. The correct option is:

The Tyndall effect is observed only when the following conditions are satisfied:

(A) The diameter of the dispersed particle is much smaller than the wavelength of the light used.
(B) The diameter of the dispersed particle is not much smaller than the wavelength of the light used.
(C) The refractive indices of the dispersed phase and the dispersion medium differ greatly in magnitude.
(D) The refractive indices of the dispersed phase and the dispersion medium are almost similar in magnitude.