The nitrate ion NO3- has a molecular geometry known as trigonal planar. In this structure, the nitrogen atom is at the center, and it is bonded to three oxygen atoms, which are evenly spaced around it at 120-degree angles. The nitrogen atom has a formal charge of +1, and each oxygen atom has a formal charge of -2/3. The overall charge of the ion is -1, as indicated by the negative sign.In terms of polarity, the nitrate ion is a polar molecule. The nitrogen-oxygen bonds are polar due to the difference in electronegativity between nitrogen 3.04 and oxygen 3.44 . However, the trigonal planar geometry of the ion results in the bond dipoles canceling each other out, making the molecule symmetric and giving it an overall nonpolar character.