- A solution is a homogeneous mixture of two or more substances in which the particle size is smaller than.
- Solution has a solvent and a solute as its components.
SOLVENT: The component of the solution that dissolves the other component in it (usually the component present in larger amount) is called the solvent.
SOLUTE: The component of the solution that is dissolved in the solvent (usually present in lesser quantity) is called the solute. The following are some examples of solutions:
- Air is a homogeneous mixture of gases where both the solvent and the solute are gases.
- Sugar syrup is a solution where sugar is dissolved in water using heat. So, sugar is the solute and water is the solvent and.
- Tincture of iodine is a mixture of iodine in alcohol. Here alcohol is the solvent and iodine is the solute.
Properties of a solution:
The important characteristic properties of a solution (or true solution) are as follows:
Types of solutions:
- Solution of solid in a solid. For example, brass is a solution of zinc in copper.
- Solution of solid in a liquid. Sugar solution.
- Solution of liquid in a liquid. Vinegar is a solution of acetic acid (ethanoic acid) in water.
- Solution of gas in a liquid. Soda-water is a solution of carbon dioxide gas in water.
- Solution of gas in a gas. Air is a solution of gases like oxygen, argon, carbon dioxide and water vapour, etc.
The maximum amount of a solute which can be dissolved inof a solvent at a specified temperature is known as the solubility of that solute in that solvent (at that temperature).
Effect of Temperature and Pressure on Solubility:
The effect of temperature and pressure on the solubility of a substance is as follows:
- The solubility of solids in liquids increases on increasing the temperature; and decreases on decreasing the temperature.
- The solubility of solids in liquids remains unaffected by the changes in pressure.
- The solubility of gases in liquids usually decreases on increasing the temperature; and increases on decreasing the temperature.
- The solubility of gases in liquids increases on increasing the pressure; and decreases on decreasing the pressure
Saturated and Unsaturated Solutions:
Depending upon the amount of solute present in a solution, it can be called a dilute, concentrated or a saturated solution.
- Unsaturated Solution: A solution in which more quantity of solute can be dissolved without raising its temperature.
- Saturated Solution: A solution in which no more solute can be dissolved at that temperature.
Effecting of ‘Heating’ and ‘Cooling’ on a Saturated Solution:
- If a saturated solution at a particular temperature is heated to a higher temperature, then it becomes unsaturated.
- If a saturated solution available at a particular temperature is cooled to a lower temperature, then some of its dissolved solute will separate out in the form of solid crystals.
Concentration of a solution:
The concentration of a solution is the amount of solute present in a given quantity of the solution. Solute and solvent are present in uneven ratios in solutions.
Concentration of solution = Amount of solute/Amount of solution
Concentration of solution = Amount of solute/Amount of solvent
It can be deducted in the following ways:
- Mass by mass percentage of a solution:
- Mass by volume percentage of a solution:
- Volume by volume percentage of solution: