chemistry-class-11-unit-04-chapter-07-chemical-bonding-molecular-structure-l-7-7-vmo4mfr38nw

### <Success style="font-size:25px"> Chemical Bonding Molecular Structure L-7 </Success>
### <primary style="font-size:24px"> Molecular orbital diagram </primary>
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- $He_{2}$
- $Be_2$
- There is no bond in $Be_2$ example - $Be_2$ molecule does not exist

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<footer style = "font-size: 18px"> $\rightarrow$ Chemical bonding molecular structure $\rightarrow$ <span style = "color:blue"> Molecular orbital diagram </span> $\rightarrow$ Molecular orbital diagram $\rightarrow$ Mixing of orbitals </footer>

### <Success style="font-size:25px"> Chemical Bonding Molecular Structure L-7 </Success>
### <primary style="font-size:24px"> Molecular orbital diagram </primary>
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- $B_2$ - $1s^2$ , $2s^2$ $2p^1$ 
 - $B.O$ = $\frac{2}{2}$ = $1$
 - $B_2$ is not diamagnetic , experimentally $B_2$ paramagnetic
- $C_2$ - it has 12 electrons

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<footer style = "font-size: 18px">Chemical bonding molecular structure $\rightarrow$ Molecular orbital diagram $\rightarrow$ <span style = "color:blue"> Molecular orbital diagram </span> $\rightarrow$ Mixing of orbitals $\rightarrow$ Mixing of orbitals </footer>

### <Success style="font-size:25px"> Chemical Bonding Molecular Structure L-7 </Success>
### <primary style="font-size:24px"> Mixing of orbitals </primary>
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- Energies of orbitals should be similar
- Symmetries of orbitals should be same
- For $ Li_2$ to $N_2$
 - Mixing of 2s with 2p orbital
 - The mixing of orbitals depend upon effective nuclear charge $Z^{*}$
 - $Z^{*}$ increases from left to right

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<footer style = "font-size: 18px">Molecular orbital diagram $\rightarrow$ Molecular orbital diagram $\rightarrow$ <span style = "color:blue"> Mixing of orbitals </span> $\rightarrow$ Mixing of orbitals $\rightarrow$ Molecular orbital diagram </footer>

### <Success style="font-size:25px"> Chemical Bonding Molecular Structure L-7 </Success>
### <primary style="font-size:24px"> Molecular orbital diagram </primary>
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<main>

- For $B_2 - 1s{^2}\hspace{1mm} 2s{^2}\hspace{1mm}2p{^1}$
 - Bond order = 1
 - $B_2$ is paramagnetic

- For $C_2$ - number of electrons are 12
 - Bond order = $\frac{4-0}{2}$ = 2
 - $C_2$ is diamagnetic

- For $N_2$ - number of electrons are 14
 - Bond order = $\frac{6-0}{2}$ = 3
 - $N$ $\equiv$ $N$
 
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<footer style = "font-size: 18px">Mixing of orbitals $\rightarrow$ Molecular orbital diagram $\rightarrow$ <span style = "color:blue"> Molecular orbital diagram </span> $\rightarrow$ Molecular orbital diagram $\rightarrow$ Molecular orbital diagram </footer>

### <Success style="font-size:25px"> Chemical Bonding Molecular Structure L-7 </Success>
### <primary style="font-size:24px"> Molecular orbital diagram </primary>
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- For $O_2$ - there are two unpaired electrons example - it is paramagnetic
 - According to valence bond theory , $O_2$ is diamagnetic
 - So , this is the failure of valence bond theory
 - According to MOT , 1 electron is enough for bond formation 
- HOMO is (highest occupied molecular orbital)
- LUMO is (lower unoccupied molecular orbital)

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<footer style = "font-size: 18px">Molecular orbital diagram $\rightarrow$ Molecular orbital diagram $\rightarrow$ <span style = "color:blue"> Molecular orbital diagram </span> $\rightarrow$ Molecular orbital diagram $\rightarrow$ Molecular orbital diagram </footer>

### <Success style="font-size:25px"> Chemical Bonding Molecular Structure L-7 </Success>
### <primary style="font-size:24px"> Molecular orbital diagram </primary>
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- $O_2^{2-}$ $\hspace{2mm}$ $O_2^{-}$ $\hspace{2mm}$ $O_2^{+}$
- $O_2+2electron \rightarrow$ $O_2^{2-}$ 
- For $O_2$
 - Bond order = 2
 - Bond length = 121pm
- For $O_2^{2-}$
 - Bond order = 1
 - Bond length = 149pm

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### <Success style="font-size:25px"> Chemical Bonding Molecular Structure L-7 </Success>
### <primary style="font-size:24px"> Molecular orbital diagram </primary>
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- For $O_2^{+}$
 - Bond order = $\frac{6-1}{2}$ = 2.5
 - $O-O$ = 112pm
- $O_2^{+}$ $>$ $O_2$ $>$ $O_2^{-}$ $>$ $O_2^{2-}$
- $2.5$ $>$ $2$ $>$ $1.5$ $>$ $1$ (Bond order)
- $112pm$ $<$ $121pm$ $<$ $126pm$ $<$ $149pm$ (Bond length)

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