Molecular Orbitals of Oxygen

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

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

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

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

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

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.

Which of the following species is the least stable

1. $O_2$
2. $O_2^{-2}$
3. $O_2^{+1}$
4. $O_2^{-1}$

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

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

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

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

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

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

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