Dipole Moment AAMC 5 Q 111

[Driven3]

Which of the following properties is associated with the existence of glycine as a dipolar ion in aqueous solution?

A) High dipole moment
B) Nonanswer
C) Nonanswer
D) Low solubility in water


The answer is presented as A. How is this so? Could not a dipolar ion such as glycine have equal and cancelling charges on both ions? Further, glycine is nonpolar, and by definition, doesn't a high dipole moment make something polar?

I'm clearly incorrect somewhere. Please help.

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[DrknoSDN]

I would start by eliminating D as an option because the nitrogen and oxygen can hydrogen bond with water making it soluble. (24.99 g/100 mL @wikipedia)

Also a high dipole moment is caused when one side of the molecule has a very electron withdrawing group (COOH), and the other has a donating group (NH2).

The charges charged version containing COO- and NH3+ would not cancel each other out but try and hydrogen bond. The COO- with hydrogens in (aq) and the NH3+ with the oxygen.