Polar Covalent Bond
In the covalent compound if one is the more is more electronegative than other atom, then shared pair of electrons is attracted towards more electronegative atom so it acquire or obtain some partial negative charge which is represented by delta negative (d-) and other atom acquire some partial positive charge which is represented by delta positive (d+) therefore polar bond is form, which is known as Polar covalent bond.
Example : Hydrogen Chloride Molecule.
In HCl molecule, Chlorine is more electronegative than Hydrogen so chlorine acquires partial negative charge and hydrogen acquire partial positive charge.
Characteristics of Polar Covalent Compounds
i. Polar covalent compounds are approximately 80% covalent and 20% ionic so they so characteristics of both covalent and ionic (or electrovalent) compounds.
ii. In solution forms, polar covalent compounds are good conductor of electricity. Example: HCl
iii. As compared to pure non-polar covalent compounds and electrovalent compounds, the melting point and boiling point of polar covalent compound are higher.