• $:\ddot O = C =\ddot{O} {:}$

• $E_{e l} \propto \frac{Q_1 \times Q_2}{d}$

• $H_A+H_B \rightarrow H-H$

Distance between two hydrogen atom is 74pm

• $\ H_A \frac{74 p m}{} H_B$

• $74 \mathrm{pm}$ is called bond length

• Energy is $-432 \mathrm{~kJ} / \mathrm{mol}$

• $432 \mathrm{~kJ} / \mathrm{mol}$ of energy is to be given to cleave the $\mathrm{H}_2$

• $432 \mathrm{~kJ} /$ mol is the bond energy of the bond in $\mathrm{H}-H$ molecule

• $\ H_A \frac{74 p m}{} H_B$ this bond is called covalent bond

Covalent bond - Sharing of pair of electrons between two atoms

Ionic bond - Type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound such a bond forms when the valence (outermost) electrons of one atom are transferred permanently to another atom

Metallic bond - Shared electrons are delocalized

Boron has 3 valence electron which can be shown like this

• $\dot{.B.}$

Carbon has 4 valence electrons which can be shown like this

• $:C:$

• 2 $\times$ H+ 0 = 0
• 2 $\times$ 1 + 6 = $8{e^-}$
• Total electrons = 8

• Central atom is the one has the greatest bonding capacity

• Valence electrons
• $C+H+3 Cl$
• 4+1 $+$ $\underbrace{3 \times 7}_{21}$
• $26 V e^{-}$
• 4 Single bonds = 4 $\times$ 2 = 8$e^{-}$
• 26 - 8 = 18$e^{-}$
• 4 Single bonds
• 9 Lone pairs

• valence electrons
• $C+2H+0$

• $4+2\times1+6$
• $12 e^{-}$