The sum of bond order of $O_2^{+}$,$O_2^{-}$,$O_2$ and $O_2^{2+}$ is equal to

The number of electrons that are paired in an oxygen molecule $(O_2)$ is:

$N_2$ and $O_2$ are converted into $N_2^+$ and $O_2^+$ respectively. Which of the following is not correct?

Fill in the blanks given below:
$(i)$ The Molecular Orbital Theory was proposed by .......... and .......... scientists.
$(ii)$ The addition of atomic orbitals results in the formation of ............ orbitals.
$(iii)$ The distribution of electrons in molecular orbitals is called .......... .
$(iv)$ The number of bonds between atoms joined by a covalent bond is called .......... .

Which of the following species is not paramagnetic?

Which of the following molecules does not exist on the basis of Molecular Orbital Theory?