Question

How do polar and nonpolar covalent bonds and polar and nonpolar molecules compare? How do they contrast?

Answer 1

Compare and contrast between bonds and molecules of polar and non-polar:

• Non-polar covalent bonds are a type of covalent bond in which a pair of electrons is shared with each other between two atoms.

• Polar covalent bond is a type of covalent bond in which pair of electrons are not equally shared between two atoms. We can also say bonds are polar when one element in a compound is more electronegative than the other.

• The bond shared in the compound of carbon dioxide between carbon and oxygen atoms is non-polar covalent bond whereas the shared in the compound of water between hydrogen and oxygen atom is polar-covalent bond.

• Polar molecules are those molecules where there is an “electronegativity difference between the bonded atoms”.

• For eg: Water -
  `H_(2)O`, Ammonia -
  `NH_(3)`, Sulfur dioxide -
  `SO_(2)`, Hydrogen sulfide -
  `H_(2)S`, Ethanol -
  `C_(2)H_(6)O`, etc.

• Non-polar molecules are those molecules sharing equal electrons between “atoms of a diatomic molecule” or large molecule cancel each other.

• For eg: Carbon dioxide -
  `CO_(2)`, Benzene -
  `C_(6)H_(6)`, Carbon tetrachloride -
  `CCl_(4)`, Methane -
  `CH_(4)`, Ethylene -
  `C_(2)H_(4)`, etc.