Is NH4+ polar or non polar?

It is symmetrical in three dimensions so it is non-polar.

To determine whether NH4+ (ammonium ion) is polar or nonpolar, we need to look at the molecular geometry and the polarity of its constituent bonds.

The NH4+ ion consists of one nitrogen atom bonded to four hydrogen atoms. Nitrogen has five valence electrons and forms four single bonds with the hydrogen atoms through the sharing of electrons.

The shape of the NH4+ ion is tetrahedral, with the nitrogen atom at the center and the four hydrogen atoms forming a symmetric tetrahedron around it. In this geometry, the individual bonds are arranged in a way that cancels out the dipole moments, resulting in a nonpolar molecule.

However, it's important to note that while the NH4+ ion itself is nonpolar, the nitrogen-hydrogen bonds within the ion are polar due to the difference in electronegativity between nitrogen (3.04) and hydrogen (2.20). This means the individual bonds have a polar character, but the overall molecular structure is nonpolar due to the symmetry and cancellation of dipole moments.

So, to answer the question directly, NH4+ is a nonpolar molecule.