What is the meaning of the “like dissolve like” rule in chemistry?
In chemistry, the “like dissolves like” rule refers to solubility and polar and non-polar substances.
Remember: “Solute” means the substance that is dissolved into a larger substance (the solvent). But in more accurate terms: The solute in a solution is the one with the fewest number of moles, and the solvent is the one with the largest number of moles. Think of dissolving 2 grams of sugar in a large cup of 50 grams of water.
In basic terms, the rule says that most typically, polar solutes can dissolve in polar solvents and non-polar solutes can dissolve in non-polar solvents. But, polar solutes rarely dissolve in non-polar solvents and vice versa. A great example of this is looking at water which is polar and oil which is non-polar: They just do not mix.