How do compounds consisting of polar molecules dissolve?

In the case of compounds of polar molecules dissolved in water, I know it's to do with the formation of permanent dipole force of interactions between the water molecules and the polar molecules. But how exactly does dissolution happen? I've thought about it, and the only reasoning that comes to mind is that the London forces between the polar molecules break, as it is weaker than the force between the water and polar molecule, although I'm not sure if this is the reason why..




Dissolving a substance in water means breaking hydrogen bonds. It requires energy. If enough new hydrogen bonds are made between solute molecules and water, this dissolution is energetically favorable. This happens when the solute is polar. If not enough new hydrogen bonds are made, the entropy effect is not sufficient to counterbalance the enthalpy effect : the substance will not be soluble in water.


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