Respuesta :
Evaporation is called a surface phenomenon because water molecules present on the surface of liquid are bonded weakly as compared to inner molecules and when temperature increase hydrogen bonding between molecules break .Due to this water molecules tend to evaporation so that's why evaporation called the surface phenomenon.
evaporation- the surface of the liquid is heated slowly and eventually becomes a gas
boiling- the entire liquid is heated and the entire liquid becomes a gas