Solubility of a substance is its maximum amount that can be dissolved in a specified amount of solvent at a specified temperature. Solubility of a substance depends upon the nature of solute and solvent as well as temperature and pressure. A saturated solution is a solution that is in equilibrium with an excess of solid at a given temperature. A solution that contains a high concentration of solute than does a saturated solution is known as supersaturated solution. If a small crystal of solute is added to a supersaturated solution, the solid will at once crystallize out and an equilibrium will be established. This is known as seeding. More the dielectric constant of a solvent, more is the solubility of polar covalent or ionic compounds in it. Some covalent compounds dissolve in water due to hydrolysis while some other covalent solids dissolve in water due to hydrogen bonding. Ionic compounds dissolve in polar solvents while covalent compounds dissolve in non-polar solvents and this is known as like dissolves like.

The solubilities of ionic compounds often but not always increase with temperature, because energy is required to pull the molecules or ions away from the crystal lattice (lattice energy) \(\Delta H_L\).

Energy is also liberated due to solvation of the solute particles. If the solvent is water, the energy liberated due to solvation is known as hydration energy \(\Delta H_h\).

The energy change when one mole of ionic compound dissolves in water is \(\Delta H_{sol}\).

\[\Delta H_{sol} = \Delta H_h - \Delta H_L\]

Since the hydration energies of the ions and the lattice energy are exothermic changes, they have a negative sign. If \(\Delta H_h\) is more than \(\Delta H_L\), then \(\Delta H_{sol}\) will be negative and the ionic crystal dissolves exothermically.

In liquid CCl₄ which of the following has maximum solubility

I₂

The correct answer is option 3.  I₂.

CCl₄ is a non-polar solvent, so the solutes that will dissolve in it must also be non-polar. Cl₂, Br₂, and I₂ are all non-polar molecules, but I₂ is the largest and has the strongest intermolecular forces. This means that I₂ will have the highest solubility in CCl₄. NaCl is an ionic compound, so it will not dissolve in CCl₄.

Additional Information:

Solvent-solute interactions

The solubility of a solute in a solvent is determined by the solvent-solute interactions. Solvent-solute interactions are the forces of attraction between the solvent molecules and the solute molecules. In the case of CCl₄, the solvent molecules are non-polar. This means that the solvent-solute interactions are van der Waals forces.

Intermolecular forces of solutes

The intermolecular forces of a solute are the forces of attraction between the solute molecules. The solutes that will dissolve in CCl₄ must also be non-polar. This is because the solvent-solute interactions must be similar in order for the solute molecules to interact with the solvent molecules and form a solution.

Size of solute molecules

The size of the solute molecules also affects their solubility in CCl₄. The larger the solute molecules, the stronger the van der Waals forces between them. This means that larger solute molecules will have a higher solubility in CCl₄.

Iodine

Iodine is the largest of the three halogens (Cl₂, Br₂, and I₂). This means that iodine has the strongest van der Waals forces and the highest solubility in CCl₄.

In conclusion, I₂ has the maximum solubility in CCl₄ because it is a non-polar solute with large molecules and strong van der Waals forces.