According to molecular orbital theory, which of the following will not be a viable molecule?
He2+
H2-
H22-
He22+
Answer: (C)
Explanation for correct option:
(C)ElectronicconfigurationofH22-=(σs2)(σ*s2)BondorderofH22-=Nb-Na2=2-22=0Ifabondorderofzeroisobtained,thatmeansthatthemoleculeistoounstableandsoitwillnotexist.
Explanation for incorrect option:
(A)ElectronicconfigurationofHe2+=(σs2σ*s1)Bondorder=Nb-Na2=2-12=0.5BondorderofHe2+is0.5.Becauseoption(A)isincorrect(B)ElectronicconfigurationofH2-=(σs2σ*s1)Bondorder=Nb-Na2=2-12=0.5BondorderofH2-is0.5.Becauseoption(B)isincorrect(D)ElectronicconfigurationofHe22+=(σs2)Bondorder=Nb-Na2=2-02=1BondorderofHe22+is1.Becauseoption(D)isincorrect
Hence option (C) is the correct option.