Explain the differences among nonpolar covalent bonds, polar covalent bonds, and ionic bonds.

Nonpolar covalent bonds are a type of chemical bond where 2 atoms share electrons with each other.
Polar covalent bonds are the same as nonpolar covalent bonds, but a pair of electrons are unequally shared between 2 atoms. 
Ionic bonds are a type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound.

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