What is the difference between Boiling and Evaporation? Gas and Vapour?

 What is the difference between Boiling and Evaporation? Gas and Vapour?

Edited and Contributed by
R Kesavamurthi

Founder
IGNITING YOUNG MINDS (IYM)
9952419531
https://ignitingyoungminds.in

Qn1: What is difference between boiling and evaporation ?

Qn2: Why do we sprinkle water on the roof or open ground in summer?

Qn3: What is the difference between gas and vapour?

 

Qn:1

Boiling and evaporation are two different processes:

 

Boiling

1. Rapid vaporization: Boiling occurs when a liquid is heated to its boiling point, causing rapid vaporization.

2. Bubble formation: Bubbles of vapor form within the liquid and rise to the surface.

3. Constant temperature: Boiling occurs at a constant temperature, which is the boiling point of the liquid.

 

Evaporation

1. Slow vaporization: Evaporation is a slower process that occurs when a liquid is heated, but not necessarily to its boiling point.

2. Surface vaporization: Evaporation occurs only at the surface of the liquid.

3. Temperature-dependent rate: The rate of evaporation depends on the temperature, humidity, and other environmental factors.

 

In summary, boiling is a rapid, bubble-forming process that occurs at a constant temperature, while evaporation is a slower, surface-based process with a temperature-dependent rate.

Application of Evaporation:

Puddles in the road side after one or two days empties itself through evaporation, a slow process aided by sun light, wind velocity, atmospheric temperature. No matter where the puddle is,  whether in 35°C Chennai or 25°C Coimbatore or 15°C Ooty, evaporation still takes place but slower in Ooty compared to Chennai.

 

 

Qn:2

We sprinkle water on the roof or open ground in summer to cool the area through evaporation. As the water evaporates, it absorbs heat from the surroundings, thereby reducing the temperature. This process is known as evaporative cooling.

 

 

Qn:3

The key differences between gas and vapor are:

 

Gas

1. State of matter: A gas is a distinct state of matter.

2. Composition: Can be a single substance (e.g., oxygen) or a mixture (e.g., air).

3. Expansion: Gases expand to occupy their containers.

4. Temperature and pressure: Gases can exist at any temperature and pressure.

 

Vapor

1. State of matter: Vapor is a transition state between liquid and gas.

2. Composition: Typically a single substance (e.g., water vapor).

3. Expansion: Vapors can expand, but they often condense back into liquids.

4. Temperature and pressure: Vapors usually exist below the critical temperature and pressure of the substance.

 

In summary, all vapors are gases, but not all gases are vapors. Vapors are gases that are in the process of transitioning from a liquid state or can condense back into a liquid, whereas gases are a more general state of matter.