hydration shells

A hydration shell is a layer of water molecules that surrounds and interacts with a dissolved substance, like an ion or molecule, in a solution. These water molecules arrange themselves around the solute based on electrical attractions, stabilizing it and preventing it from clumping with others. This primary layer of water, the hydration shell, influences how substances behave in water, affecting processes like chemical reactions and biological functions. Essentially, it's the water’s way of "caring for" and stabilizing dissolved particles, forming a protective or stabilizing barrier around them.