posted by Bob .
You are heating water in a pot on the stove. Shortly before the water boils properly, bubbles of steam begin rising from the bottom of the pot but vanish before they reach the water’s surface. What happened to those bubbles?
They condense back into liquid water. When steam condenses to water that releases latent heat. So, these bubbles when they condense into water are transerring heat from the bottom to the water near the surface.