Molecular orbitals are formed by the overlap of atomic orbitals. Two atomic orbitals combine atom from two molecular orbitals called vonding molecular orbital (BOM) and anti bonding molecular orbital (ABMO). Energy of anti bonding orbital is raised above the parent atomic orbitals that have combined and the energy of the bonding orbital is lowered than the parent atomic orbitals. Energies of various molecular orbitals for elements hydrogen to nitrogne increase in the order :
`sigma_(1s)ltsigma_(1s)^(**)ltsigma_(2s)ltsigma_(2s)^(**)lt(pi_(2py)~~pi_(2py))lt sigma_(2py)lt(pi_(2py)^(**)~~pi_(2py)^(**))ltsigma_(2pz)^(**)` and for ozygen and fluorine order of energy of molecular orbitals id given below :
`sigma_(1s)ltsigma_(1s)^(**)ltsigma_(2s)ltsigma_(2s)^(**)ltsigma_(2pz)lt(pi _(2px)^(**)~~pi_(2py)^(**))sigma_(2pz)^(**)`
Different atomic orbitals of one atom combine wiht the atomic orbitals of the second atom whihc have comparable energies and proper orientation. Further, if the overlapping is head on, the molecular orbital is called 'Sigma' `(sigma)` and if the overlap is atreal, the molecular orbital is called 'pi', `(pi).` The molecular orbitals are filled with electrons according to the same rules as followed for filling of atomic orbitals. However, the order for filling is not the same for all molecules or their ions, Bond order is one the most ipmrtaint parameters to compare the strength of bonds.
Which of the following statements is correct ?