Features of Liquids:

• Liquids do not have a definite shape.
• Liquids have fixed volumes.
• They can change their shape.
• Their intermolecular force of attraction is less than solids.
• The kinetic energy of its particles is more than solids.

Physical Classification of States of Matter

The physical classification of states of matter refers to categorizing substances based on their physical properties and behavior. The four main states of matter are solid, liquid, gas, and plasma. However, the physical classification does not include the colloidal state.

Solid State:
- Solids have a definite shape and volume.
- The particles in solids are tightly packed and vibrate in fixed positions.
- They have strong intermolecular forces, resulting in high density and low compressibility.
- Examples of solids include ice, wood, and metals.

Liquid State:
- Liquids have a definite volume but take the shape of their container.
- The particles in liquids are close together but can move past each other.
- They have weaker intermolecular forces compared to solids, resulting in moderate density and compressibility.
- Examples of liquids include water, oil, and alcohol.

Gaseous State:
- Gases have neither a definite shape nor a definite volume.
- The particles in gases are far apart and move freely.
- They have weak intermolecular forces, resulting in low density and high compressibility.
- Examples of gases include air, oxygen, and carbon dioxide.

Plasma State:
- Plasma is an ionized gas consisting of positive ions and free electrons.
- It does not have a definite shape or volume.
- Plasma is formed at high temperatures or by the application of electric fields.
- Examples of plasma include lightning, stars, and neon signs.

Colloidal State:
- Colloids are a type of mixture where particles are dispersed in a continuous medium.
- The particles in colloids are larger than those in solutions but smaller than those in suspensions.
- Colloids can exhibit properties of both solids and liquids.
- Examples of colloids include milk, fog, and gelatin.

Conclusion:
The physical classification of states of matter includes solid, liquid, gas, and plasma. However, the colloidal state is not considered a separate state of matter in this classification. Colloids are classified as mixtures rather than distinct states due to their intermediate properties between solutions and suspensions.