Suspension refers to a heterogeneous mixture in which the soluble components are insoluble and suspended. In other words, a suspension is a heterogeneous mixture of solid particles that can settle due to their large size.
For example: Sometimes, in the right light, you can see dust particles floating in the room. Eventually, the dust settles on the floor and furniture, and the room needs to be cleaned. Dust in the air is a suspension, or to better understand this, if you go to a beach and mix sand and water in a bucket, you have formed a suspension system and, depending on the time, the sand settles on the bottom of the bucket. It is possible to keep the water clear.
Suspensions are turbid solutions because the molecules of the solute in them are larger than the solvent and therefore light does not pass through them and are also unstable, meaning that after a short time the solid particles separate from the liquid and accumulate at the bottom of the container.
Suspensions are thermodynamically unstable but can be kinetically stable over a longer period of time, which in turn can determine the durability of the system. This time is measured to provide accurate information to the consumer and ensure the best product quality. The difference between a suspension system and a colloid is that the solid particles in their system disappear over time.
The source of this article is the Persian section of the site, which you can read if you are fluent in Persian: سوسپانسیون