What are polar covalent bonds?
What are polar covalent bonds?
Polar covalent bonds and molecules :
When a covalent bond is formed between heteronuclear molecules such as in HCl, the shared pair of electrons gets displaced towards the atom which is more electronegative. As a result, one end becomes slightly positively charged while the other end becomes slightly negatively charged.
These type of bonds are called polar covalent bonds and the molecules are known as polar covalent molecules.
In the hydrogen chloride (HCl) molecule, hydrogen and chlorine atoms are bonded through electrons sharing.
The shared pair of electrons lies more towards Cl atom (because Cl is more electronegative). Therefore, Cl atom acquires a slight negative charge (-δ) and H atom, a slight positive charge (+δ).
The O-H bond in water (H2O) is also a polar bond – the hydrogen atom has a slight positive charge, and oxygen atom has been the slight negative charge, i.e., H+δ- O-δ. The compounds having polar covalent bonds undergo ionization when dissolved in any polar solvent, such as water. Such polar compounds in solutions produce free ions. For example, when hydrogen chloride (HCl) is dissolved in water, it ionizes to produce H3O+(hydronium ion) and Cl- (chloride ion).
H2O + H+δ → Cl-δ → H2O….. H+δ…… Cl-δ→ H3O+ + Cl-
Polar covalent bonds and molecules :
When a covalent bond is formed between heteronuclear molecules such as in HCl, the shared pair of electrons gets displaced towards the atom which is more electronegative. As a result, one end becomes slightly positively charged while the other end becomes slightly negatively charged.
These type of bonds are called polar covalent bonds and the molecules are known as polar covalent molecules.
In the hydrogen chloride (HCl) molecule, hydrogen and chlorine atoms are bonded through electrons sharing.
The shared pair of electrons lies more towards Cl atom (because Cl is more electronegative). Therefore, Cl atom acquires a slight negative charge (-δ) and H atom, a slight positive charge (+δ).
The O-H bond in water (H2O) is also a polar bond – the hydrogen atom has a slight positive charge, and oxygen atom has been the slight negative charge, i.e., H+δ- O-δ. The compounds having polar covalent bonds undergo ionization when dissolved in any polar solvent, such as water. Such polar compounds in solutions produce free ions. For example, when hydrogen chloride (HCl) is dissolved in water, it ionizes to produce H3O+(hydronium ion) and Cl- (chloride ion).
H2O + H+δ → Cl-δ → H2O….. H+δ…… Cl-δ→ H3O+ + Cl-
