Chemistry: Suspensions and Separation Methods

A suspension is a heterogeneous mixture with particles larger than $1000\,nm$. Examples include water and soil, water and calcium carbonate, and alcohol and salt.

Properties of Suspensions:

• Heterogeneous: Composition not uniform.

• Unstable: Particles settle under gravity.

• Filtration: Particles can be separated using filter paper.

Separation Techniques:

1. Hand Picking: Manual isolation of particles (e.g., stones from rice).

2. Winnowing: Uses air to separate lighter and heavier particles (e.g., husk from wheat).

3. Sedimentation and Decantation: Heavier particles settle when undisturbed.