A true solution is a homogeneous solution in which the solute particles have diameters less than 10-7cm. i.e., the solute particles are of molecular dimensions. The particles are invisible even under powerful microscopes.
For example, sodium chloride in water is a true solution. Most ionic compounds form true solutions in water. Organic compounds like sugar and urea also form true solutions in water.
Suspensions
A suspension is a heterogeneous mixture in which one or more components have a particle size greater than 10-5cm. Very often these particles are visible to the naked eye.
For example, sand in water, sodium chloride in benzene, turmeric in water etc.
Colloids
A colloid is a solution in which the particle size ranges between 10-7 and 10-5 cm.
For example, milk, blood, honey, smoke, ink, gum, starch solution etc.
Difference between true solutions, suspensions and colloids
