* Iodine: Iodine molecules are nonpolar and held together by London dispersion forces (weak temporary dipoles).
* Carbon tetrachloride: CCl₄ is also a nonpolar molecule, primarily held together by London dispersion forces.
Why this matters:
* Like dissolves like: This principle states that polar solvents dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes.
* Intermolecular Force Compatibility: Since both iodine and carbon tetrachloride are nonpolar, their London dispersion forces are compatible. They can interact with each other, allowing the iodine molecules to disperse evenly throughout the CCl₄ solvent.
In contrast:
* Iodine is insoluble in water (H₂O), a polar solvent. This is because the strong hydrogen bonding in water cannot effectively interact with the nonpolar iodine molecules.
Key takeaways:
* The solubility of a substance depends on the strength and type of intermolecular forces present in both the solute and solvent.
* Nonpolar solvents, like carbon tetrachloride, are good solvents for nonpolar solutes, like iodine.
* Polar solvents, like water, are good solvents for polar solutes.
