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How do polar water molecules help dissolve ionic substances?

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Bohr model diagram of a hydrogen atom showing a green nucleus labeled H, a single electron orbit, and text with atomic mass 1.008 and electron configuration 1. — atom The Bohr model describes the structure of atoms, in this case hydrogen.

Water molecules are polar because they have an angular shape, which prevents the bond dipole moments of the oxygen-hydrogen bonds from canceling out. This polarity is essential for dissolving ionic substances through a process called hydration.12

When an ionic solid is placed in water, the water molecules orient themselves around the ions to minimize energy:
* The positive ends (hydrogen atoms) of the water molecules are attracted to the anions of the solid.2
* The negative end (oxygen atom) of the water molecule is attracted to the cations.2

These strong water-ion interactions replace the forces holding the ions together in the solid crystal, causing the salt to break apart and dissolve. As the ions separate, they become surrounded by a shell of water molecules, forming a hydrated ion. This ability to stabilize ions is why water is an effective solvent for many ionic compounds.231