Condensation Experiment for Schools, Teachers, and Students
Condensation is the process by which a gas or vapor changes into a liquid state upon cooling or compression. It is the reverse of evaporation or boiling and involves the release of heat energy.
Theory:
- When a gas or vapor is cooled, its particles lose energy and come closer together due to intermolecular forces. This causes the gas to transition into the liquid state.
- During condensation, the temperature of the gas remains constant as it releases latent heat of vaporization.
- Condensation occurs when the gas temperature reaches its dew point or under compression where pressure increases.
Latent Heat of Condensation:
The latent heat of condensation is the amount of heat energy released when 1 unit mass of gas or vapor changes into a liquid without any change in temperature. The formula is:
Q = mL
Where:
- Q: Heat released (J)
- m: Mass of the gas or vapor (kg)
- L: Latent heat of condensation (J/kg)
Conditions for Condensation:
- Cooling of the Gas: Lowering the temperature brings the vapor to its dew point, triggering condensation.
- Compression of the Gas: Increasing pressure forces gas particles to come closer, promoting condensation.
- Presence of surfaces or dust particles helps the vapor condense as droplets (nucleation).
Examples of Condensation:
- Formation of water droplets on the surface of a cold glass.
- Dew formation on leaves and grass during early morning due to cooling of air.
- Clouds form when water vapor in the atmosphere cools and condenses on dust particles.
- Fog formation occurs when water vapor near the ground condenses in cool air.
Applications of Condensation:
- Distillation Process: Condensation is used to collect the liquid after evaporation during distillation.
- Refrigeration and Air Conditioning: Vapors are condensed back into liquids in cooling cycles.
- Power Plants: Steam in turbines is condensed back into water in condensers for reuse.
- Water Cycle: Condensation plays a key role in the formation of clouds and precipitation.
Observations:
- During condensation, the temperature remains constant as latent heat is released.
- Condensation occurs more effectively when the gas is cooled below its dew point.
- The latent heat released during condensation warms the surroundings.
- Condensation requires surfaces (like dust particles) to act as nuclei for droplet formation.
