Question

How do you define solubility?

Answer 1

There are different factors which are responsible for the effect in solubility of a material. The concentration of solute in a solution, and the interaction between the particles of the solute and the solvent helps us define the property of the solute.

Complete step-by-step answer: Solubility of a solute can be defined as the part of the solute which gets dissolved in a considered amount of solvent, under the conditions of standard temperature and pressure. In other words, it can be defined as the amount of the solute which is provided to us, in terms of grams or number of moles that could be dissolved in a hundred gram of a given solvent in order to get a saturated solution under the conditions of standard temperature and pressure.
There are various factors which affect the solubility of a solution. We will be considering them now.
The first factor is the interaction between the solvent and the solute particles, meaning, stronger the solute solvent interaction, higher will be the solubility, and weaker the interaction between the solute and solvent, lower will be the value of solubility.
The second factor could be the temperature at which the solution is present. Although the effect of the temperature generally depends on the nature of the reaction, meaning it is an exothermic or endothermic reaction. In case of endothermic reactions, as the temperature is increased the solubility also increases. While in case of exothermic reactions, the solubility decreases with increase in temperature.
The third factor is the pressure. Henry's law establishes a relationship between the solubility of gases in solvent. According to the law, at constant temperature, with decrease in partial pressure of a gas, the concentration of the gas in the solvent also decreases and consequently the solubility also decreases.

Note: The solubility of a solid in liquid depends on whether the reaction is endothermic or exothermic, as the endothermic reaction would prefer increase in temperature and the solubility will increase, while in case of exothermic reaction, with increase in the temperature of the reactant the solubility would decrease.