Short Answer

Condensation is the process in which a gas changes into a liquid when it is cooled. During condensation, gas particles lose energy, move more slowly, and come closer together, forming a liquid. This happens because cooling increases the attraction between the particles, causing them to settle into the liquid state.

Common examples of condensation include water droplets forming on a cold glass, steam turning into water on a bathroom mirror, and clouds forming in the sky. Condensation is a reversible physical change and is the opposite of evaporation and boiling.

Detailed Explanation :

Condensation

Condensation is a physical process in which a gas changes into a liquid when heat is removed. It occurs because the gas particles lose energy on cooling, slow down, and come close enough for the intermolecular forces to pull them together, forming a liquid. This process is commonly seen in everyday life and plays an important role in the water cycle, weather formation, and many industrial activities.

Condensation is the reverse of evaporation and boiling. While evaporation changes a liquid into a gas, condensation changes a gas back into a liquid. Even though the state changes during condensation, the chemical composition of the substance remains the same. For example, both steam and water are made of H₂O molecules.

How Condensation Happens

1. Cooling of Gas Particles

Gas particles move very fast and are far apart from each other. When a gas is cooled:

• The particles lose energy.
• Their movement slows down.
• They come closer due to the stronger force of attraction.

This closeness allows the gas to change into a liquid.

2. Loss of Kinetic Energy

The speed of gas particles depends on their kinetic energy. Cooling removes kinetic energy from the particles. As a result:

• Particles collide less strongly.
• They cannot stay far apart.
• They begin to stick together.

This reduced motion is the main reason gas turns into liquid.

3. Formation of Liquid Droplets

During condensation, tiny droplets of liquid form as gas particles come together. These droplets gather and grow larger.

Examples:

• Water droplets on the lid of a cooking pot.
• Dew drops on grass in early morning.
• Fog forming near the ground.

These droplets show that gas has converted into liquid.

4. Condensation Temperature

Condensation usually occurs when a gas is cooled to a specific temperature. This may or may not be the same as the boiling point of the liquid. When the gas reaches this temperature:

• It begins turning into liquid.
• Further cooling increases condensation.
• Temperature remains constant while the state is changing.

For example, steam condenses into water when cooled below 100°C.

Examples of Condensation in Daily Life

Condensation is seen in many everyday activities:

1. Dew Formation

In the early morning, water vapor in the air condenses on cool surfaces like grass and leaves, forming dew. This happens because the surface temperature becomes low enough to cool the water vapor.

2. Mist on a Cold Glass

When a cold glass is taken out of the refrigerator, tiny water droplets appear on its outer surface. The cold glass cools the surrounding air, causing water vapor to condense on it.

3. Clouds in the Sky

Clouds are formed when warm, moist air rises, cools, and condenses into tiny droplets. These droplets gather to form clouds.

4. Steam on Bathroom Mirrors

After a hot shower, the mirror becomes foggy because steam from hot water condenses on the cool mirror surface.

5. Water on the Lid While Cooking

When food is cooked, steam rises and touches the cooler lid of the pot. The steam condenses and forms water droplets on the lid.

Importance of Condensation

Condensation is important for many natural and human activities:

1. Water Cycle

Condensation is a key step in the water cycle. It helps in cloud formation, which leads to rain and maintains the balance of water on Earth.

2. Cooling Systems

Refrigerators and air conditioners use condensation in their working process to cool surfaces and air.

3. Purification of Water

Distillation uses evaporation and condensation to separate pure water from impurities.

4. Weather Formation

Fog, clouds, and rain are formed because of condensation.

Difference Between Condensation and Evaporation

• Condensation: Gas → Liquid
• Evaporation: Liquid → Gas

Both are reversible changes and depend on temperature and particle movement.

Conclusion

Condensation is the process where a gas changes into a liquid by losing heat. This happens when gas particles slow down, come closer, and form liquid droplets. Condensation is essential in natural processes like cloud formation and the water cycle, as well as in daily activities such as dew formation and cooling systems. It is a reversible physical change that helps us understand how matter behaves with changes in temperature.