Which of the following is planar due to back bonding?

What is meant by the term bond order? Explain.

How many molecular orbitals filled with one or more electrons are present in $N_2^+$?

Why is $KO_{2}$ paramagnetic?

For $F_2$ and $OF$ molecules,consider the following statements:
$(a)$ Bond order for both is one
$(b)$ $OF$ is paramagnetic but $F_2$ is diamagnetic
$(c)$ $F_2$ is more likely to dissociate into atoms than $OF$
$(d)$ Both have greater number of electrons in $BMO$ than that in $ABMO$
Which of the following statements are true $(T)$ or false $(F)$ respectively?

Which of the following statements are correct for the peroxide ion $(O_{2}^{2-})$?
$(i)$ It has a bond order of $1$.
$(ii)$ It is diamagnetic.
$(iii)$ It has four completely filled antibonding molecular orbitals.
$(iv)$ It is isoelectronic with neon.