What is the meaning of the term “like dissolves like?”
The correct answer and explanation is:
The phrase “like dissolves like” refers to the principle that solvents dissolve solutes with similar chemical properties. More specifically, polar solvents tend to dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes. This is due to the intermolecular forces at play between the solvent and solute molecules.
When a substance dissolves in a solvent, the molecules of the solute interact with the molecules of the solvent. For polar solutes, such as salt or sugar, the solvent molecules also need to be polar, as they can form strong dipole-dipole interactions or hydrogen bonds with the solute molecules. In the case of water, which is a highly polar solvent, it is effective at dissolving other polar substances because of the strong attraction between water molecules and the solute molecules.
Nonpolar substances, such as oils or fats, do not interact well with polar solvents like water. Instead, they dissolve in nonpolar solvents like hexane or benzene. This happens because nonpolar molecules rely on London dispersion forces (weak, temporary attractions between molecules), which are more effectively facilitated by other nonpolar molecules.
For example, when you try to mix oil and water, the oil forms separate layers because the water molecules are more attracted to each other than to the oil molecules, and vice versa. On the other hand, when oil is mixed with a nonpolar solvent like hexane, both dissolve readily due to similar intermolecular forces.
Thus, “like dissolves like” reflects the idea that substances with similar polarity or molecular structure tend to mix or dissolve with each other more readily than substances with dissimilar properties.