States of Matter in Our Tiny Particle Universe

Matter, the fundamental substance composing the universe, is the cornerstone of our understanding of the physical world. Everything in the universe that is composed of both mass and volume, meaning they occupy space and have weight is called matter. The matter is made up of very tiny particles and these particles are so small that we cannot see them with naked eyes.

Particle Nature of Matter: Particle Nature with Dettol Drops

• Made of Millions of Particles: The particles of the matter are really small as there are millions of tiny particles in just one crystal, any particle, which keep on dividing themselves into smaller and smaller particles. 
  • Example: This can be visually seen when a drop of dettol is added to water.

Characteristics of Particles of Matter: Space, Motion, and State of Matter

• Space Between Particles: The particles of one type of matter get into the spaces between particles of the other, proving that there is enough space between particles of matter. 
  • Example: When we make tea, coffee or lemonade (Nimbu Paani ), particles of one type of matter get into the spaces between particles of the other.
• Constant Motion of Particles: Particles of the matter are in constant motion and this movement is due to the kinetic energy they possess, which depends on the temperature. 
• Attractive Force: Particles of matter have force acting between them, which keeps them together. 
  • The strength of this force of attraction varies from one kind of matter to another.

States of Matter: Solid, Liquid, and Gaseous States

• Variation in the characteristics of the particles of matter creates variation in states of matter. 
• There are three different states of matter i.e. solid, liquid and gas.

The Solid State: Matter’s Stability in States

• Matter Occurs in Solid State.  Solids maintain their state with strong intermolecular forces, which keeps the particles in a fixed position.
• Characteristics of Solid State: It include definite shape and volume, distinct boundaries and negligible compressibility.

The Liquid State: Liquids in the Realm of States

• Lack Shape: The liquids have no fixed shape but have a fixed volume. 
• Binding Force: Liquids have weaker intermolecular forces compared to solids, allowing them to flow and take the shape of their container. 
• Diffusion: Their rate of diffusion is higher than that of solids because liquid particles move freely and have greater space between each other than the solids.

The Gaseous State: States of Matter in Expansive Gas

• Binding Force: Gases have neither a definite shape nor a definite volume, they have very weak intermolecular forces, allowing them to expand to fill the entire volume of their container. 
• Compressibility: Due to their high compressibility, large volumes of a gas can be compressed into a smaller volumes (eg. CNG, LPG cylinder).
• Particle Gap: The particles in gasses are widely spaced and move randomly at high speeds exerting pressure.

Heat and Change: States of Matter Through Temperature

Temperature: States of matter Through Temperature Changes 

• Fusion/Melting: When the temperature of solids increases, the kinetic energy of particles rises causing them to vibrate more rapidly. 
  • Heat energy provided overcomes interparticle forces, enabling particles to move freely and transition from a solid to a liquid, this change of state from solid to liquid is called fusion or melting.
• Melting Point: The minimum temperature at which a solid melts to become a liquid at the atmospheric pressure is called its melting point.
  • The melting point of a solid is an indication of the strength of the force of attraction between its particles.
• Latent Heat of Fusion: When a solid melts, its temperature remains the same because the heat energy is being used to overcome particle attraction hence showing no change in temperature. 
  • This is the latent heat of fusion which is defined as the heat energy required to change 1 kg of solid into liquid at its melting point. 
  • This shows that particles in water at 0℃ (273 K) have more energy as compared to particles in ice at the same temperature.

• Latent Heat of Vaporization: When heat is supplied to water, particles gain energy and eventually reach a point where they can break free, causing the liquid to change into a gas.
  •  During this transition the temperature change remains hidden, the excess energy is absorbed by the particles and is called as latent heat of vaporization.
• Sublimation: It involves change directly from solid to gas, this process of change directly, without an intermediate liquid state, from solid to gas is called sublimation.
• Deposition: When a substance changes from gas to solid, the process is called deposition.

Effect of Change of Pressure: Transforming Gases in States of Matter

• Applying pressure and reducing temperature can liquefy gases.
•  Example: Solid carbon Dioxide (known as Dry ice)  gets converted directly into gaseous state at atmospheric pressure without coming into liquid state.

Conclusion:

Hence, we can conclude that pressure and temperature determine the state of a substance, whether it will be solid, liquid or gas.

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