Properties of Solids and Liquids

Solids and liquids are two different states of matter that vary in their properties in various aspects. We’re always surrounded by solids and liquids, in one or the other form, in their condensed phases. Solids have a fixed arrangement of molecules, whereas liquids don’t have a fixed arrangement; they can freely flow.

Liquids are fluids, but solids do not come under the category of fluids. We can change a solid into liquid or liquid into a solid without making any changes in its chemical composition. In this article, you will explore the different properties of solids and liquids. Refer to the properties of solids and liquids study material below to learn more about these states of matter.

Properties of Solids and Liquids

• Molecular Structure: Molecules of solids are very tightly packed and closely bound with a regular arrangement, whereas, in liquids, molecules are bound closely but not so much that their bonds can’t be broken easily and have an irregular arrangement. Solids don’t have enough energy to overcome the strong intermolecular forces, which causes them to be tightly packed. This is why solids have a crystalline structure.
• Mass, Shape & Volume: Solids and liquids both have a definite mass. Solids, having a fixed and tightly packed intermolecular structure, have a fixed shape and occupy a fixed space, whereas liquids take the shape of the container they are put into. Because solids have a fixed shape, the particles inside them vibrate back and forth around a fixed axis. On the other hand, particles in liquids have a free moment but are still attracted to each other. Solids and Liquids both have a fixed volume.
• Fluidity: Solids do not possess the properties of fluids; they don’t flow easily, whereas Liquids fall under the category of fluids, where they flow from a higher level to a lower level.
• Compressibility: Solids can not be compressed easily because of their strong intermolecular bonds. Similarly, liquids don’t possess the property of compressibility because their molecular structure is not very tightly packed.
• Rigidity: Solids are highly rigid, whereas liquids are much less rigid than solids.
• Diffusion: Diffusion occurs very slowly in solids, whereas it is faster in liquids. Solids have the least kinetic energy.
• Interparticle Forces: Solids have strong and definite interparticle forces, and hence a higher force of attraction between the particles, whereas these forces are slightly weak in liquids. Due to their strong intermolecular forces, solids have high intermolecular energy; liquids don’t.
• Density: Solids are denser than liquids by an average of 10%. Liquids possess surface tension, capillary action, and viscosity, which solids don’t. Mercury is one of such liquids.
• Boiling and Melting points: Liquids have higher boiling and melting points, greater than the room temperature. Water below 0°C is in solid form, and between 0°C-100°C, it is a liquid.

Illustration of the properties

• Even though rubber changes its shape, it falls under the category of solids. It changes shape when a pull force is applied to it, but it also has a reaction force that brings back the rubber to its original shape. Hence, rubber has a fixed shape since it satisfies all other properties of solids.
• Sugar and salt are solids that have extremely small crystals. They don’t appear to be solids since they dissolve in the water, which means that they take the shape of the container. However, it is not so; because of their small size, they get dissolved in water.
• Hydrogen bonding causes the water to expand when it is kept frozen.

Conclusion

This study material and notes for the topics properties of solids and liquids discusses the properties of the condensed phase. Solids have a fixed shape and volume and are incompressible. Solids have strong intermolecular forces of attraction, higher density and higher rigidity. On the other hand, solids have comparatively lower intermolecular forces. They don’t possess fluidity, a higher rate of diffusion, and a high boiling rate. We’ve also discussed some of the examples of solids and liquids above, along with their properties.