TS EAMCET 19-July-2022 Shift 2 Solved Paper

If the bond order of species is zero, then species will not exist.
Bond order
H2+−σls1‌‌∴ Bond order =‌

1−0

2

=0.5
He22+−σs2‌‌∴ Bond order =‌

2−0

2

=1
Li22−−σ1s2,σ*1s2,σ2s2,σ*2s2
∴ Bond order =‌

4−4

2

=0 (do not exist )
‌Ne2:σls2,σ*1s2,σ2s2,σ*2s2,σ2pz2,π2px2
‌‌≈2py2,π*2px2≈π*2py2,σ*2pz2
∴ Bond order =‌

10−10

2

=0 (do not exist)
Be2−−σ1s2,σ*1s2,σ2s2,σ*2s2,π2px1≈π2py0
∴ Bond order =‌

5−4

2

=0.5
He2−σls2,σ*ls2
∴ Bond order =‌

2−2

2

=0( do not exist )
Hence, Li22−,Ne2 and He2 will not exist.