What is a Suspension? (Definition and Examples)

A suspension is a heterogeneous mixture containing solid particles that are large enough to be seen by the naked eye. Unlike a true solution (where particles dissolve completely, like sugar in water), the particles in a suspension do not dissolve. Instead, they remain suspended throughout the bulk of the medium for some time, and eventually settle down at the bottom if left undisturbed.

1. Muddy Water: Mud or soil mixed with water. The heavy soil particles will slowly settle to the bottom if the glass is left still.
2. Chalk Powder in Water: The white chalk particles float around but do not dissolve.
3. Flour in Water: Wheat flour (atta) stirred into water creates a cloudy suspension.
4. Antibiotic Syrups for Kids: Many liquid medicines come as dry powder that must be mixed with water. They often have 'Shake Well Before Use' printed on the bottle because the medicine particles settle at the bottom (they are a suspension).
5. Sand in Water.

• Heterogeneous: The mixture is not uniform throughout.
• Particle Size: The particles are relatively large (greater than 100 nm in diameter).
• Visibility: Particles can be easily seen with the naked eye.
• Filtration: Because the particles are large, they can be separated from the mixture using a simple filter paper.
• Tyndall Effect: If you shine a laser or flashlight through a suspension (before the particles settle), the particles will scatter the beam of light, making the path of light visible.