NEET 2015 Physics and Chemistry Paper

According to molecular orbital theory as bond order decreases stability of the molecule decreases.
Bond order =‌

1

2

(Nb−Na)
Bond order of O2+=‌

1

2

(10−5)=2.5
Bond order of O2=‌

1

2

(10−6)=2
Bond order of O2−=‌

1

2

(10−7)=1.5
Bond order of O22−=‌

1

2

(10−8)=1.0
Hence the correct order is O2+>O2>O2−>O22−