Molecular Orbitals of Oxygen

Q. Which one of the following $O_2^{-},O_2^{2-}$ may exhibit paramagnetism?

1. $O_2^{-}$
2. $O_2^{2-}$
3. Both are paramagnetic
4. Both are diamagnetic

Q. The total number of electrons in all bonding molecular orbitals of $O_2^{2-}$ is
(Round off to the Nearest Integer).

Q. Which of the following pairs of species have the same bond order?

1. $CO,NO$
2. $O_2,N{O}^{+}$
3. $C{N}^{-},CO$
4. $N_2,O_2^{-}$

Q. The number of unpaired electrons in $O_2$ molecule is:

1. Zero
2. 1
3. 2
4. 3

Q.

According to molecular orbital theory, the species among the following that do not exist are:

1. ${{\mathrm{He}}_2}^{-}$

2. ${{\mathrm{He}}_2}^{+}$

3. ${\mathrm{O}}_2^{2-}$

4. ${\mathrm{Be}}_2$

Q. The energy of $\sigma 2p_z$ molecular orbital is greater than $\pi 2p_x$ and $\pi 2p_y$ molecular orbitals in nitrongen moleculae. Write the complete sequence of energy levels in the increasing order of energy in the moleculae. Compare the relative stability and the magnetic behaviour of the following species:

$N_2,N_2^{+},N_2^{-},N_2^{2+}$

Q.

Which is more covalent $\mathrm{NaCl}\mathrm{or}\mathrm{CuCl}$?

Q. Number of unpaired electrons present in $O_2^{2-}$ is:

1. $0$
2. $2$
3. $1$
4. $3$

Q. In the formation of $O_2^{+}$ from $O_2$, the electron is removed from:

1. $\sigma -$ orbital
2. $\pi -$ orbital
3. ${\pi }^{\ast }-$ orbital
4. ${\sigma }^{\ast }-$ orbital

Q.

In $O_2^{-}$, $O_{2}and{O}_2^{2-}$ molecular species, the total number of anti-bonding electrons respectively are:

1. 7, 6, 8

2. 1, 0, 2

3. 6, 6, 6

4. 8, 6, 8

Q. The number of antibonding electron pairs in $O_2^{-2}$ molecular ion on the basis of molecular orbital theory is -

1. $3$
2. $2$
3. $5$
4. $4$

Q. In $P{O}_4^{3-}$ ion, the effective charge on each oxygen atom and the $P-O$ bond order respectively are:

1. −0.75, 1.25
2. - 0.75, 1.0
3. - 0.75, 0.6
4. - 3, 1.25

Q. During the change of $O_2$ to $O_2^{-}$ ion, the electron is added to which one of the following orbital?

1. ${\pi }^{\ast }$ orbitals
2. ${\sigma }^{\ast }$ orbitals
3. $\sigma$ orbitals
4. $\pi$ orbitals

Q.

What are the different rules for filling up the orbitals? Explain each rule in detail.

Q. What is effective atomic number (EAN)?
Calculate EAN of cobalt $(Z=27)$ in $\left[CO\right(N{H}_3{)}_6{]}^{+3}$ and of zinc $(Z=30)$ in $\left[Zn\right(N{H}_3{)}_4]S{O}_4$

Q. Arrange the following species in the increasing order of their magnetic moment.
(I) $VC{l}_3$ (II) $VOS{O}_4$ (III) $N{a}_{3}V{O}_4$ (IV)

$\left[V{\left(H_{2}O\right)}_6\right]S{O}_4.H_{2}O$

1. III < II < I < IV
2. III < IV < III < I
3. II < III < I < IV
4. IV < I < II < III

Q. What is a lone pair of electrons, explain with suitable example?

Q.

Name an element that has two shells, each one of which is completely filled with electrons.

Q. An atom of an element has 2, 8, 11, 2 electrons in K, L, M and N shells respectively. The total number of s-electrons in the atom are:

1. 1
2. 6
3. 8
4. 10

Q.

Carbon forms million of compounds because of its tetravalent and capacity of _ ?

Q.

In $O_2^{-}$, $O_{2}and{O}_2^{2-}$ molecular species, the total number of anti-bonding electrons respectively are:

1. 1, 0, 2

2. 7, 6, 8

3. 6, 6, 6

4. 8, 6, 8

Q. According to VBT any covalent bond will be formed by overlapping of valence atomic orbitals of bonded atoms provided atomic orbitals must be half–filled and electrons be in opposite spin.
According to type of overlapping covalent bonds can be classified as: (a) $\sigma$ bond (b) $\pi$ bond (c) $\delta$ bond.
Which of the following set of orbitals does not produce nodal plane in $xz–$plane?

1. $d_{yz}+d_{yz}$
2. $d_{xy}+d_{xy}$
3. $p_y+d_{xy}$
4. None of these

Q. In $P{O}_4^{3-}$ ion, the effective charge on each oxygen atom and the $P-O$ bond order respectively are:

1. −0.75, 1.25
2. - 0.75, 1.0
3. - 0.75, 0.6
4. - 3, 1.25

Q. The number of unpaired electrons in $O_2$ molecule is:

1. Zero
2. 1
3. 2
4. 3

Q. The formal charge on central oxygen atom in $O_3$ molecule is :

1. $0$
2. $+1$
3. $-1$
4. $-2$

Q. Arrange the following orbitals in the order in which they are filled with electrons.
$6s,5d,6p,7s,5f$

1. $6s<6d<5d<5f<7s$
2. $6s<5d<6p<7s<5f$
3. $6s<7s<5d<5f<6p$
4. $6d<5f<6s<6p<7s$

Q. If ${\Delta }_0<P$, the correct electronic configuration for $d^4$ system will be:

1. $t_{2g}^2{e}_g^2$
2. $t_{2g}^4{e}_g^0$
3. $t_{2g}^3{e}_g^1$
4. $t_{2g}^0{t}_g^4$

Q. a. $p-O_{2}N-C_6{H}_4-\stackrel{+}{C}{H}_2$
b. $p-C{H}_{3}O-C_6{H}_4-\stackrel{+}{C}{H}_2$
c. $p-Cl-C_6{H}_4-\stackrel{+}{C}{H}_2$
d. $C_6{H}_5-\stackrel{+}{C}{H}_2$
Correct order of stability of above species is:

1. b > a > c > d
2. b > d > c > a
3. c > d > a > b
4. a > b > c > d

Q. Order of enol content is:

Q.

Give reasons for the following:

A molecule of Carbon tetrachloride has four single covalent bonds.