What are the differences between boiling and evaporation?

Answer 1

Boiling- i) It is a bulk phenomena.

ii) The substance changes it's state only at it's boiling point.

iii) It doesn't give a cooling effect.

Evaporation- i) It is a surface phenomena.

ii) The substance does not change only at it's boiling point.

iii) It gives a cooling effect.
EVAPORATION

• evaporation takes place silently
• it takes place at all temp.
• its a natural process
• it takes place only on surface
• rate of evaporation depends on area of free surface

BOILING

• its associated with characteristic sound
• its takes place at all temp.
• to be heated for boiling
• at constant temp. boiling takes place
• boiling takes place at all regions of liquid
• it does not depend on free surface

Answer 2

Some key points are

1) Evaporation takes internal energy while for boiling we have to provide external energy or we have to reduce the pressure.

2) As Evaporation takes internal energy therefore evaporation results in cooling while this is not observed in boiling.

3) Evaporation occurs below saturated temperature while Boiling occurs at and above saturated temperature.

4) Evaporation occurs at liquid-vapor interface while Boiling occurs at solid liquid interface.

5) Vapor bubbles are formed in Boiling while in Evaporation there are no bubble formation and no bubble motion.

6) There are different regimes of boiling (like nucleate boiling, transition boiling, film boiling etc.) while these regimes are not present in Evaporation.

7) Rate of Evaporation is much slower than the Boiling.

8) Example of Evaporation are

Water in a lake at 20°C, evaporates to air at 20°C and 60 percent relative humidity since the saturation pressure of water at 20°C is 2.34 kPa, and the vapor pressure of air at 20°C and 60 percent relative humidity is 1.4 kPa. Other examples of evaporation are the drying of clothes, fruits, and vegetables; the evaporation of sweat to cool the human body; and the rejection of waste heat in wet cooling towers.

i am hoping that the above comparison will give you the clear picture about the evaporation and boiling.

Answer 3

Boiling occurs when a liquid turns into vapor throughout the entire liquid, forming bubbles. Evaporation, on the other hand, happens at the surface of a liquid as individual molecules escape as vapor. Boiling requires the liquid to reach its boiling point, while evaporation can occur at any temperature.