[Chemistry Class Notes] on Saturated Solution Pdf for Exam

Saturation, any of several physical or chemical conditions defined by the existence of an equilibrium between pairs of opposing forces or of an exact balance of the rates of opposing processes. 

Common Saturated Solution examples include the condition of a solution left in contact with the pure undissolved solvent until there is no further change in solution concentration, and the state of a vapour equally left in contact with the substance’s pure solid or liquid form.

The water is saturated in the first case, when the rate at which the pure substance dissolves to join the solution in the solvent is precisely equal to the rate at which the dissolved substance exits the solution (e.g. by crystallising).

The rate at which the completely condensed (liquid or solid) substance vaporises in the second example is exactly the rate at which the vapour condenses.

A Saturated Solution or vapour contains the greatest concentration of a dissolved or vaporised substance that can be obtained under specified pressure and temperature conditions. While supersaturation (a condition in which concentration reaches the equilibrium value) can be brought on in certain situations, these solutions or vapours are unstable and spontaneously return to the Saturated state.

Factors Affecting Saturated Solution:

The amount of solute that can be dissolved to form a Saturated Solution in a solvent depends on a variety of factors. The most prominent considerations are:

Temperature: With temperature, the solubility decreases. For example, salt can be dissolved in hot water much more than in cold water.

Pressure: Increasing pressure in solution can force more solute. This is widely used to remove liquid gases.

Chemical Composition: Solubility affects the nature of the solute and solvent and the involvement of other contaminants in a solution. For instance, in water, you can dissolve much more sugar than salt. Ethanol and water are mutually completely soluble.

Types of Saturation:

When solid solute (substance or particles) and liquid solvent are mixed, the only possible reactions are dissolution and crystallisation.

There are three types of saturation. They are:

• Saturated Solution: It is a solution where the maximum amount of solute is, so much so that if there was any more, it would not dissolve.

• Unsaturated Solution: It is a solution where the solute concentration is lesser than its corresponding equilibrium solubility. This means that the amount of solute is in lesser amounts than the maximum value until the solution reaches its saturation level. 

• Supersaturated Solution: It contains more dissolved solute than required for making a Saturated solution. It is formed by heating a Saturated solution, then adding more solute, and then cooling it down. The excess dissolved solute crystallises with the seeding of supersaturated solution with crystals of the solute.
  

How to Make a Saturated Solution

There’s more than one way to make the Saturated Solution. You may be able to prepare it from scratch, saturate an unsaturated solution, or cause a supersaturated solution to remove any product.

Until it stops dissolving, add solute to the liquid.

Evaporate the solvent until it becomes saturated from the solution. Once the solution begins to crystallise or precipitate it will saturate the solution.

Add a seed crystal to a super – Saturated Solution so that extra solvent will grow onto the crystal, leaving the solution Saturated.

Examples of Saturated Solutions

• Soda is a source containing soluble carbon dioxide in water. Therefore carbon dioxide gas produces bubbles when the pressure is released.

• Adding chocolate powder to milk produces a Saturated Solution so it prevents dissolving.

• When molten butter or oil, salt can be applied to the stage where the salt grains avoid dissolving and create a Saturated Solution.

• A Saturated Solution can be produced if you give sufficient sugar to your coffee or tea. You’ll know when the sugar starts dissolving, you’ve reached the saturation point. Hot tea or coffee helps you absorb a lot more sugar than you can add to a cold drink.

• To form a Saturated Solution, sugar can be applied to the vinegar.

Therefore, these are everyday examples of Saturated Solutions.