Suspension

When we add salt to water, it dissolves. So, it becomes a solution.

But, when we add sand to water, it doesn't dissolve. Then, it becomes a suspension.

What is Suspension?

It is a heterogeneous mixture of small particles of solid in liquid

In this case, particles of solid do not dissolve in liquid  but spread throughout the liquid

Example 1

Mixture of chalk and Water

Chalk particles do not dissolve in water but spread evenly throughout the water

Example 2

Mixture of Sand and Water

Sand Particles do not dissolve in water, they spread evenly throughout the water

Properties of Suspension

• It is heterogeneous mixture
• Size of solid particles is comparatively large (more than 100 nm) , so they can be seen easily
• Particles can be separated by filtration (using filter paper)
• Particles are not stable , they settle down after some time
• It shows  Tyndall Effect ; if a beam of light passes through a suspension, it scatters it