Have you heard your parents talk about the concentration of a particular solution? It is a daily life discussion in almost every household. And, mind you, we are not talking about the concentration that you are asked to put in your studies! In this chapter, we let you put your concentration on learning about the concentration of a solution!
What do you mean by Concentration of a Solution?
The concentration of a solution is the amount of solute present in a given quantity of the solution. In other words, the concentration of a solution is the mass of solute in grams present in 100 g of the solution. Based on this definition, there are two main types of solutions.
The solution that has a small amount of solute is called Dilute Solution. The solution that has a large amount of solute is called Concentrated Solution. This is a very narrow division of solutions. Let us now look at the types of solution in more depth.
- Saturated Solution: A saturated solution is one in which you cannot dissolve any more quantity of solute at a given temperature. It means that this kind of solution already contains the maximum amount of solute that you can dissolve in it at a given temperature.
- Unsaturated Solution: An unsaturated solution is one in which you can dissolve more quantity of solute at a given temperature.
Browse more Topics under Is Matter Around Us Pure
- Physical and Chemical Changes
- What are the Types of Pure Substances?
- Introduction and What is a Mixture?
- Separating the Components of Mixture
- What is a Solution?
- What is a Colloidal Solution?
- What is a Suspension?
Test for Saturation
In order to test whether or not a given solution is saturated, we should add some more solute to this solution and try to dissolve it by stirring. If it does not dissolve, then it will be a saturated solution but if it dissolves, then it is an unsaturated solution. However, if a particular saturated solution at a particular temperature is heated to a higher temperature, then it becomes unsaturated.
Why Does This Happen? This happens because on applying more heat, the solubility of solute increases. Thus, you can dissolve more of solute by raising the temperature of the solution. If you cool a saturated solution to a lower temperature, then some of its dissolved solutes separate out in the form of solid crystals. This is because the solubility of the solute in the solution decreases on cooling.
The Solubility of a Solution
The solubility of a solute in a solvent is the maximum amount of a solute that dissolves in 100 g of a solvent at a specified temperature. For example, you can dissolve 36 g of NaCl in 100 g of water at 20°C. Therefore, the solubility of NaCl in water is 36 g at 20°C. To be able to calculate the solubility of a substance, we need to find the mass of substance dissolved in 100g of water.
Effect of Temperature and Pressure on Solubility
- The solubility of solids in liquids increases upon increasing the temperature and decreases upon decreasing the temperature. Therefore, the temperature has a direct effect.
- The solubility of solids in liquid remains unaffected by any changes in pressure. Therefore, the pressure will have no effect.
- Pressure has a direct effect on the solubility of gases in liquids. Therefore, the solubility of gases in liquid increases on increasing the pressure and decreases on decreasing the pressure.
Solved Example For You
Question: Discuss the effect of temperature on the solubility of gases.
Answer: Temperature has an indirect effect on the solubility of gases in liquids. Therefore, the solubility of gases in liquid usually decreases when we increase the temperature. It increases in decreasing the temperature.