What is Boiling & Evaporation ? :: āĻ¸ā§āĻĢ⧁āϟāύ āĻŦāύāĻžāĻŽ āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ












1. Definition / āϏāĻ‚āĻœā§āĻžāĻž

i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ): Rapid change of liquid into vapour throughout the liquid. (āϤāϰāϞ⧰ āϏāĻŽā§āĻĒā§‚ā§°ā§āĻŖ āĻ…āĻ‚āĻļāϤ āĻĻā§ā§°ā§āϤāĻ—āϤāĻŋāϤ āĻŦāĻžāĻˇā§āĻĒāϞ⧈ āĻĒā§°āĻŋā§ąāĻ°ā§āϤāύāĨ¤)


ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ): Slow change of liquid into vapour from the surface only. āĻ•ā§‡ā§ąāϞ āĻĒ⧃āĻˇā§āĻ ā§° āĻĒā§°āĻž āϧ⧀⧰āĻ—āϤāĻŋāϤ āĻŦāĻžāĻˇā§āĻĒāϞ⧈ āĻĒā§°āĻŋā§ąāĻ°ā§āϤāύāĨ¤



2. Temperature / āωāĻˇā§āĻŖāϤāĻž: i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ):Occurs at a fixed boiling point. (āύāĻŋāĻ°ā§āĻĻāĻŋāĻˇā§āϟ āĻ¸ā§āĻĢ⧁āϟāύāĻžāĻ‚āĻ•āϤ āϘāĻŸā§‡āĨ¤), ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ): Occurs at any temperature. (āϝāĻŋāϕ⧋āύ⧋ āωāĻˇā§āĻŖāϤāĻžāϤ āϘāϟāĻŋāĻŦ āĻĒāĻžā§°ā§‡āĨ¤)

 

3. Place of Occurrence / āĻ•’āϤ āϘāĻŸā§‡: i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ): Happens throughout the liquid. (āϏāĻŽā§āĻĒā§‚ā§°ā§āĻŖ āϤāϰāϞāϤ āϘāĻŸā§‡āĨ¤), ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ)Happens only at the surface. (āĻ•ā§‡ā§ąāϞ āĻĒ⧃āĻˇā§āĻ āϤ āϘāĻŸā§‡āĨ¤)

 

4. Speed / āĻŦ⧇āĻ—: i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ): Fast process. (āĻĻā§ā§°ā§āϤ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻžāĨ¤), ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ)Slow process. (āϧ⧀⧰ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻžāĨ¤)

 

5. Bubble Formation / āĻŦ⧁āĻĻāĻŦ⧁āĻĻ āϏ⧃āĻˇā§āϟāĻŋ: i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ): Bubbles are formed. (āĻŦ⧁āĻĻāĻŦ⧁āĻĻ āϏ⧃āĻˇā§āϟāĻŋ āĻšāϝāĻŧāĨ¤) ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ)No bubbles are formed. (āĻŦ⧁āĻĻāĻŦ⧁āĻĻ āϏ⧃āĻˇā§āϟāĻŋ āύāĻšāϝāĻŧāĨ¤)

 

6. Effect / āĻĒā§ā§°āĻ­āĻžā§ą: i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ): No cooling effect. (āĻļā§€āϤāϞāϤāĻž āϏ⧃āĻˇā§āϟāĻŋ āύāϕ⧰⧇āĨ¤)  ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ)Produces cooling effect. (āĻļā§€āϤāϞāϤāĻž āϏ⧃āĻˇā§āϟāĻŋ āϕ⧰⧇āĨ¤)

 

7. Example / āωāĻĻāĻžāĻšā§°āĻŖ: i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ): Water boiling in a pot. (āĻĒāĻžāϤāĻŋāϞāϤ āĻĒāĻžāύ⧀ āĻĢ⧁āĻŸā§‹ā§ąāĻžāĨ¤)  ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ)Drying of wet clothes. (āĻ­āĻŋāϜāĻž āĻ•āĻžāĻĒā§‹ā§° āĻļ⧁āĻ•ā§‹ā§ąāĻžāĨ¤)

 

Main Difference / āĻŽā§āĻ–ā§āϝ āĻĒāĻžā§°ā§āĻĨāĻ•ā§āϝ: i. Boiling (āĻ¸ā§āĻĢ⧁āϟāύ) → Rapid vapourisation throughout liquid (āĻ¸ā§āĻĢ⧁āϟāύ → āϏāĻŽā§āĻĒā§‚ā§°ā§āĻŖ āϤāϰāϞāϤ āĻĻā§ā§°ā§āϤ āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ),           

ii. Evaporation (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ) → Slow vapourisation from surface (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ → āĻĒ⧃āĻˇā§āĻ ā§° āĻĒā§°āĻž āϧ⧀⧰ āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ)




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MCQ on Boiling vs Evaporation :: āĻ¸ā§āĻĢ⧁āϟāύ āφ⧰⧁ āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ⧰ āĻ“āĻĒā§°āϤ MCQ


1. Boiling is the rapid change of liquid into: (ā§§. āĻ¸ā§āĻĢ⧁āϟāύ āĻšā§ˆāϛ⧇ āϤāϰāϞ⧰ āĻĻā§ā§°ā§āϤāĻ—āϤāĻŋāϤ āĻ•āĻŋāĻšāϞ⧈ āĻĒā§°āĻŋā§ąāĻ°ā§āϤāύ ?)

(a) Solid (b) Ice (c) Vapour (d) Crystal


Ans / āωāĻ¤ā§āϤ⧰: (c) Vapour


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: During boiling, liquid rapidly changes into vapour. (āĻ¸ā§āĻĢ⧁āϟāύ⧰ āϏāĻŽāϝāĻŧāϤ āϤāϰāϞ āĻĻā§ā§°ā§āϤāĻ—āϤāĻŋāϤ āĻŦāĻžāĻˇā§āĻĒāϞ⧈ āĻĒā§°āĻŋā§ąāĻ°ā§āϤāĻŋāϤ āĻšāϝāĻŧāĨ¤)


2. Evaporation occurs from: (⧍. āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ āĻ•’ā§° āĻĒā§°āĻž āϘāĻŸā§‡ ?)

(a) Whole liquid (b) Bottom only (c) Surface only (d) Middle part


Ans / āωāĻ¤ā§āϤ⧰: (c) Surface only


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Evaporation occurs only from the surface of a liquid. (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ āĻ•ā§‡ā§ąāϞ āϤāϰāϞ⧰ āĻĒ⧃āĻˇā§āĻ ā§° āĻĒā§°āĻž āϘāĻŸā§‡āĨ¤)


3. Which process occurs at a fixed temperature? (ā§Š. āϕ⧋āύ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻž āύāĻŋāĻ°ā§āĻĻāĻŋāĻˇā§āϟ āωāĻˇā§āĻŖāϤāĻžāϤ āϘāĻŸā§‡ ?)

(a) Evaporation (b) Boiling (c) Cooling (d) Condensation


Ans / āωāĻ¤ā§āϤ⧰: (b) Boiling


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Boiling occurs at a fixed temperature called boiling point. (āĻ¸ā§āĻĢ⧁āϟāύ āύāĻŋāĻ°ā§āĻĻāĻŋāĻˇā§āϟ āωāĻˇā§āĻŖāϤāĻžāϤ āϘāĻŸā§‡ āϝāĻžāĻ• āĻ¸ā§āĻĢ⧁āϟāύāĻžāĻ‚āĻ• āĻ•ā§‹ā§ąāĻž āĻšāϝāĻŧāĨ¤)


4. Which process can occur at any temperature ? (ā§Ē. āϕ⧋āύ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻž āϝāĻŋāϕ⧋āύ⧋ āωāĻˇā§āĻŖāϤāĻžāϤ āϘāϟāĻŋāĻŦ āĻĒāĻžā§°ā§‡ ?)

(a) Freezing (b) Boiling (c) Evaporation (d) Melting


Ans / āωāĻ¤ā§āϤ⧰: (c) Evaporation


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Evaporation can occur at any temperature. (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ āϝāĻŋāϕ⧋āύ⧋ āωāĻˇā§āĻŖāϤāĻžāϤ āϘāϟāĻŋāĻŦ āĻĒāĻžā§°ā§‡āĨ¤)


5. Which process produces a cooling effect ? (ā§Ģ. āϕ⧋āύ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻžāχ āĻļā§€āϤāϞāϤāĻž āϏ⧃āĻˇā§āϟāĻŋ āϕ⧰⧇ ?)

(a) Boiling (b) Evaporation (c) Freezing (d) Melting


Ans / āωāĻ¤ā§āϤ⧰: (b) Evaporation


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Evaporation absorbs heat from surroundings and causes cooling. (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ⧇ āϚāĻžā§°āĻŋāĻ“āĻĢāĻžāϞ⧰ āĻĒā§°āĻž āϤāĻžāĻĒ āĻļā§‹āώāĻŖ āϕ⧰āĻŋ āĻļā§€āϤāϞāϤāĻž āϏ⧃āĻˇā§āϟāĻŋ āϕ⧰⧇āĨ¤)


6. Bubble formation takes place during: (ā§Ŧ. āĻŦ⧁āĻĻāĻŦ⧁āĻĻ āϏ⧃āĻˇā§āϟāĻŋ āĻšāϝāĻŧ āϕ⧋āύ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻžāϤ ?)

(a) Evaporation (b) Condensation (c) Boiling (d) Sublimation


Ans / āωāĻ¤ā§āϤ⧰: (c) Boiling


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: During boiling, bubbles of vapour are formed inside the liquid. (āĻ¸ā§āĻĢ⧁āϟāύ⧰ āϏāĻŽāϝāĻŧāϤ āϤāϰāϞ⧰ āĻ­āĻŋāϤ⧰āϤ āĻŦāĻžāĻˇā§āĻĒā§° āĻŦ⧁āĻĻāĻŦ⧁āĻĻ āϏ⧃āĻˇā§āϟāĻŋ āĻšāϝāĻŧāĨ¤)


7. Drying of wet clothes is an example of: (ā§­. āĻ­āĻŋāϜāĻž āĻ•āĻžāĻĒā§‹ā§° āĻļ⧁āĻ•ā§‹ā§ąāĻž āϕ⧋āύ āϘāϟāύāĻžā§° āωāĻĻāĻžāĻšā§°āĻŖ ?)

(a) Freezing (b) Boiling (c) Evaporation (d) Melting


Ans / āωāĻ¤ā§āϤ⧰: (c) Evaporation


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Water slowly changes into vapour from the clothes. (āĻ•āĻžāĻĒā§‹ā§°ā§° āĻĒāĻžāύ⧀ āϧ⧀⧰⧇ āϧ⧀⧰⧇ āĻŦāĻžāĻˇā§āĻĒāϞ⧈ āĻĒā§°āĻŋā§ąāĻ°ā§āϤāĻŋāϤ āĻšāϝāĻŧāĨ¤)


8. Which process occurs throughout the liquid ? (ā§Ž. āϕ⧋āύ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻž āϏāĻŽā§āĻĒā§‚ā§°ā§āĻŖ āϤāϰāϞāϤ āϘāĻŸā§‡ ?)

(a) Evaporation (b) Boiling (c) Cooling (d) Condensation


Ans / āωāĻ¤ā§āϤ⧰: (b) Boiling


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Boiling takes place throughout the liquid. (āĻ¸ā§āĻĢ⧁āϟāύ āϏāĻŽā§āĻĒā§‚ā§°ā§āĻŖ āϤāϰāϞāϤ āϘāĻŸā§‡āĨ¤)


9. Which of the following is a slow process ? (⧝. āϤāϞ⧰ āϕ⧋āύāĻŸā§‹ āϧ⧀⧰ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻž ?)

(a) Boiling (b) Evaporation (c) Explosion (d) Burning


Ans / āωāĻ¤ā§āϤ⧰: (b) Evaporation


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Evaporation takes place slowly from the surface. (āĻŦāĻžāĻˇā§āĻĒā§€āĻ­ā§ąāύ āĻĒ⧃āĻˇā§āĻ ā§° āĻĒā§°āĻž āϧ⧀⧰⧇ āϧ⧀⧰⧇ āϘāĻŸā§‡āĨ¤)


10. Water boiling in a pot is an example of: (ā§§ā§Ļ. āĻĒāĻžāϤāĻŋāϞāϤ āĻĒāĻžāύ⧀ āĻĢ⧁āĻŸā§‹ā§ąāĻž āϕ⧋āύ āϘāϟāύāĻžā§° āωāĻĻāĻžāĻšā§°āĻŖ ?)

(a) Freezing (b) Evaporation (c) Boiling (d) Condensation


Ans / āωāĻ¤ā§āϤ⧰: (c) Boiling


Explanation / āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Water changes rapidly into vapour throughout the liquid during boiling. (āĻ¸ā§āĻĢ⧁āϟāύ⧰ āϏāĻŽāϝāĻŧāϤ āĻĒāĻžāύ⧀ āϏāĻŽā§āĻĒā§‚ā§°ā§āĻŖ āĻ…āĻ‚āĻļāϤ āĻĻā§ā§°ā§āϤāĻ—āϤāĻŋāϤ āĻŦāĻžāĻˇā§āĻĒāϞ⧈ āĻĒā§°āĻŋā§ąāĻ°ā§āϤāĻŋāϤ āĻšāϝāĻŧāĨ¤)