Question

Briefly describe the layers of organization of water around an ionic charge (i.e. anion or cation).

Answer 1

Water interacts differently with charged and polar substances than with nonpolar substances because of the polarity of its own molecules. Water molecules are polar, with partial positive charges on the hydrogens, a partial negative charge on the oxygen, and a bent overall structure. The unequal charge distribution in a water molecule reflects the greater electronegativity, or electron-greediness, of oxygen relative to hydrogen: the shared electrons of the O-H bonds spend more time with the O atom than with the Hs.

Because of its polarity, water can form an electrostatic interaction with other polar molecules and ions. The polar molecules and ions interact with the partially positive and partially negative ends of water, with positive charges attracting negative charges ,When there are many water molecules relative to solute molecules, as in an aqueous solution, these interactions lead to the formation of a three-dimensional sphere of water molecules, or hydration shell, around the solute. Hydration shells allow particles to be dispersed (spread out) evenly in water.