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Solution, Suspension and Tyndall effect

A homogeneous mixture of two or more components constitutes a solution. Tyndall effect is the dispersion of light when passed through a colloidal solution.

The Solution, Suspension and Tyndall effect

The Solution, Suspension and Tyndall effects are the mixtures involving liquids and their properties. A solution is a homogeneous mixture, while a suspension is a heterogeneous mixture. A colloid is a heterogeneous mixture but appears to be homogeneous. This occurs because of the small size of particles in the suspension. When light is passed through a colloidal solution, the particles disperse the light, thus creating the Tyndall effect.

Solution

  • The solution is a homogeneous mixture of two or more substances, such as lemonade soda water.
  • Particles in a solution are evenly distributed.
  • Solutions can be in any physical state. For instance, Solid: Alloys, Liquid: Soft drinks  and Gas: Air

Alloys

  • Alloys are two or more metals or a mixture of one metal and one non-metal and cannot be physically separated into their components. 
  • A mixture is considered a mixture because it reflects the properties of its components and can be a variable mixture. For example, brass is an alloy of about 30% zinc and 70% copper.

Components of the Solution

  • Solvent: The component of the solution dissolves the other component in it. It is usually the component present in more significant amounts.
  • Solute: It is the component of the solution that is dissolved in the solvent. It is usually present in small quantities.

Examples

  • The solution of sugar in water is sugar as solute and water as solvent. 
  • Solution of iodine in alcohol (‘tincture of iodine): It has iodine as solute and alcohol as a solvent. 
  • Aerated beverages such as soda water: Contain carbon dioxide as a Solution and water as a solvent. 

Properties of a Solution

  • A Solution is a homogeneous mixture. 
  • The particles of a Solution are more modest than 1 nm (10-9 metres) in width and can’t be seen by unaided eyes.
  • Path of light is not visible in a Solution: Tiny particle size does not scatter a beam of light passing through the solution.
  • By filtration, it is clear that one cannot separate the particles of the solution.
  • When dissolved particles are released without interruption, they do not settle down.

Concentration of a Solution

  • This is the amount of Solution (mass or volume) in a given quantity (mass or volume). Here are three ways to show the concentration of a Solution.
  • Mass in a large percentage of the Solution = Mass of solute mass of solution×100
  • Mass by volume percentage of a Solution =Mass of soluteVolume of solution×100
  • Volume by volume percentage of a Solution = Volume of soluteVolume of solution×100

Key Related Terms

  • Dilute Solution: If the proportion of the solute is small in the solution, it is called a dilute solution.
  • Concentrated Solution: If the proportion of solute is more prominent, it is called a concentrated Solution.
  • Saturated Solution: When no further Solution can be dissolved in the solution at a specific temperature, it is called a saturated solution.
  • Unsaturated Solution: When the quantity of solution present in the solution is less than the saturation level, it is called an unsaturated solution.
  • Solubility: The amount of solution in a solution that is saturated at a specific temperature is called its solubility.
  • Suspension
  • Suspension is a contrasting compound in which soluble particles do not dissolve but remain suspended throughout. The particles of the suspension are visible to the naked eye.

Properties of a Suspension

  • Particles of the heterogeneous suspension settle when left without interruption.
  • The suspension particles scatter the ray of light passing through it and show its way. 
  • The suspension breaks when the particles settle, and the light does not scatter.
  • The volume of the solvent particles in a suspension is relatively large. It measures more than 100 mm in length.
  • The suspension’s molecules are easily visible.
  • The particles in a suspension do not pass through a filter paper. Filtration can therefore separate a suspension.
  • The suspension is unsteady. After a few minutes, the particles in a suspension settle down.

Colloidal Solution

  • Colloidal particles are evenly distributed throughout the solution. Due to the relatively small size of the particles compared to the suspension, the mixture looks uniform.

Properties of a Colloid

  • It is a heterogeneous mixture. 
  • Colloids are classified according to dispersed medium and dispersed phase state (solid, liquid, or gas). The size of the colloid particles is so small that they cannot be seen individually with the naked eye. 
  • The colloids are so large that they scatter the beam of light passing through it and show its way. 
  • They can be left astray and lose the right path when the left is unmanaged.
  • They can’t be isolated from the blend by filtration.
  • Centrifugation, a unique separation technique, can be used to separate the colloidal particles.

Tyndall effect

  • Colloidal particles can scatter visible light beams. This scattering of the beam of light is called the Tyndall effect.
  • This effect can be seen when a small ray of light enters a room through a small hole. This is due to the light scattering in the air by fumes and smoke particles.
  • This effect can be seen when sunlight passes through the roof of a dense forest. Fog consists of tiny droplets of water, which act as colloidal particles scattered in the air.

Table: Common examples of colloids

Components of a colloidal solution:

  • Dispersed phase: The solute-like component of the dispersed particles in a colloid.

  • Dispersing medium: The component in which the dispersed phase is suspended.

Conclusion

The Solution, Suspension and Tyndall effects are associated with the mixtures’ types and their properties. The force of attraction between the solute and solvent is similar to that between solvent-solute. It implies that the total vapour pressure over a solution can be related to a mole of any component’s fraction. Raoult’s Law only works reasonably for the ideal solutions. The ideal solution obeys Raoult’s Law, whereas the non-ideal reaction does not obey Raoult’s Law and contains different molecules between the solute and solvent.