What does covalent and ionic bond have to do with chemical bond?

Covalent and ionic bonds are two different types of chemical bonding.  Covalent bonds involve the sharing of electrons between 2 atoms while ionic bonds involve the complete transferring of electrons from one atom to another.  Covalent bonds usually form between two nonmetals while ionic bonds usually form between a metal and a nonmetal.   
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Answer/nitrogen compounds in the soil;