what is the difference between true solution,suspension,colloids
True Solution is a homogeneous mixture of two or more substances in which substance dissolved (solute) in solvent has the particle size of less than 1 nm. They are stable as particles do not settle down when the solution is left standing. The particles are invisible even under powerful microscopes and cannot be separated through filter paper, parchment paper or animal membranes. They do not show Tyndell effect. They appear transparent. Simple solution of sugar in water, sodium chloride in water, most of ionic solids in water are examples of true solution.
Suspension is a heterogeneous mixture in which particle size of one or more components is greater than 1000 nm. This solution is an example of suspension. Contrary to True Solution, particles of suspension are big enough to be seen with naked eye. They are not stable as the particles of suspension settle under water due to influence of gravity. The particles of a suspension can neither pass through ordinary filter paper nor through animal membranes. Suspension may or may not show Tyndall effect. When mud is dissolved in water and stirred vigorously, particles of mud are distributed evenly in water. After some time, the particles of this solution settle under water due to influence of gravity. Turmeric in water, sand in water are some examples of suspensions.
Colloidal Solution appears to be homogeneous but is actually a heterogeneous mixture in which particle size of substance is intermediate of true solution and suspension i.e. between 1-1000 nm. Just like true solutions, Colloidal particles are small enough and can neither be seen through naked eye nor by an ordinary microscope. They easily pass through filter paper. But colloidal particles are big enough to be blocked by parchment paper or animal membrane. They are stable as particles do not settle down when the solution is left standing. Colloids show Tyndall effect. Smoke from a fire is example of colloidal system in which tiny particles of solid float in air.
Saturated solution is a solution that has dissolved as much solute as it is capable of dissolving. In a saturated solution, no more solute can be dissolved at a given temperature.