Solubility of Solutes and Aqueous Solutions

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	When we talk about the mixing of two or more substances together in solution we must consider solubility. Simply defined, it is a measure of how much solute will dissolve into the solvent. Not all substances will dissolve in all solvents. Understanding solubility properties will provide a basis for understanding the golden rule of solubility...Like dissolves like!
Factors Affecting Solubility
	Temperature will affect solubility. If the solution process absorbs energy then the solubility will be INCREASED as the temperature is increased. If the solution process releases energy then the solubility will DECREASE with increasing temperature.
	Molecular Size will affect the solubility. The larger the molecule or the higher its molecular weight the less soluble the substance will be. Larger molecules are more difficult to surround with solvent molecules in order to solvate the substance. In the case of organic compounds the amount of carbon "BRANCHING" will increase the solubility since more branching will reduce the size (or volume) of the molecule and make it easier to solvate the molecules with solvent.
	The Polarity of the solute and solvent molecules will affect the solubility. Generally polar solute molecules will dissolve in polar solvents and non-polar solute molecules will dissolve in non-polar solvents. The polar solute molecules have a positive and a negative end to the molecule. If the solvent molecule is also polar, then positive ends of solvent molecules will attract negative ends of solute molecules. This is a type of intermolecular force known as dipole-dipole interaction. All molecules also have a type of intermolecular force much weaker than the other forces called London Dispersion forces where the positive nuclei of the atoms of the solute molecule will attract the negative electrons of the atoms of a solvent molecule. This gives the non-polar solvent a chance to solvate the solute molecules.
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