Combination of atoms A and B that forms an anti-bonding molecular orbital is :

1. $\frac{{\mathrm{\Psi }}_{\mathrm{A}}^2}{{\mathrm{\Psi }}_{\mathrm{B}}^2}$

2. ${\mathrm{\Psi }}_{\mathrm{A}}^2\times {\mathrm{\Psi }}_{\mathrm{B}}^2$

3. ${\mathrm{\Psi }}_{\mathrm{A}}+{\mathrm{\Psi }}_{\mathrm{B}}$

4. ${\mathrm{\Psi }}_{\mathrm{A}}-{\mathrm{\Psi }}_{\mathrm{B}}$

A pair in which both species are not likely to exist is:

The number of (i) sp² hybridized carbon atoms and (ii) $\mathrm{\pi }$ bonds are present in the following compound are:

1. 7, 5

2. 8, 6

3. 7, 6

4. 8, 5

Among the following atomic orbital overlaps, the non-bonding overlap is:
 

1.		2.
3.		4.

The decreasing order of ionic character of the N-H, F-H, C-H, and O-H, is :  

The right order of increase in the ionic character of the molecules,
 LiF, K₂O, N₂, SO₂, ClF₃ is :

1. N₂ < SO₂ < ClF₃ < K₂O < LiF

2. N₂ > SO₂ > ClF₃ > K₂O < LiF

3. N₂ > SO₂ > K₂O > ClF₃ > LiF

4. LiF > K₂O < ClF₃ > SO₂ > N₂

From the perspective of molecular orbital theory, which statement is false?

1. ${\mathrm{Be}}_2$ is not a stable molecule.

2. ${\mathrm{He}}_2$ is not stable but ${\mathrm{He}}_2^{+}$ is expected to exist.

3. Bond strength of ${\mathrm{N}}_2$ is maximum amongst the homonuclear diatomic molecules belonging to the second period.

4. The order of energies of molecular orbitals in ${\mathrm{N}}_2$ molecule is: 

${\mathrm{\sigma }}_{2\mathrm{s}}<{\mathrm{\sigma }}_{2\mathrm{s}}^{*}<{\mathrm{\sigma }}_{2{\mathrm{p}}_{\mathrm{z}}}<({\mathrm{\pi }}_{2{\mathrm{p}}_{\mathrm{x}}}\approx {\mathrm{\pi }}_{2{\mathrm{p}}_{\mathrm{y}}})$
$<({\mathrm{\pi }}_{2{\mathrm{p}}_{\mathrm{x}}}^{*}\approx {\mathrm{\pi }}_{2{\mathrm{p}}_{\mathrm{y}}}^{*})<{\mathrm{\sigma }}_{2{\mathrm{p}}_{\mathrm{z}}}^{*}$

The number of sigma ($\mathrm{\sigma }$) and pi ($\mathrm{\pi }$) bonds in pent-2-en-4-yne is:

1.  13 $\mathrm{\sigma }$ bonds and no $\mathrm{\pi }$ bond

2.  10 $\mathrm{\sigma }$ bonds and 3 $\mathrm{\pi }$ bonds

3.  8 $\mathrm{\sigma }$ bonds and 5 $\mathrm{\pi }$ bonds

4.  11 $\mathrm{\sigma }$ bonds and 2 $\mathrm{\pi }$ bonds

Which of the following is the most basic oxide?

1. $A{l}_2{O}_3$

2. $S{b}_2{O}_3$

3. $B{i}_2{O}_3$

4. $Se{O}_2$

An electron-deficient compound among the following is: