What factors affect solubility?

1 Answer
Jan 22, 2017

Particle size, temperature, and intrinsic solubility.............


Some of these factors are kinetic. Clearly, large crystals will go up more slowly in a solvent than would a powder, which has much greater surface area, and thus much greater exposure ot the action of the solvent.

In general a hot solvent will dissolve more solute than a cold solvent. Why? Because dissolution involves the disruption of particle-particle interactions, and energy must be supplied to disrupt the interaction. And thus in many instances hot water is a better solvent than cold water.

Clearly intrinsic solubility is also a factor. Non-molecular solids, with strong particle-particle interaction should have intrinsically low solubility. Thus, the nature of the solute is an important factor. Water is a solvent whose properties are marked by its ability to hydrogen-bond. Solutes that are capable of hydrogen-bonding, for instance the hydrogen halides or methanol or ethanol, should display substantial water solubilities and indeed they do.

The polarity of water, the charge separation of the molecule, often allows it to solvate non-molecular solutes such as ionic solids, in that the dipoles can solvate positive ions and negative ions