Is the bubbling of a liquid caused by the rapid escape of a gas rather than by boiling?
Bubbling of a liquid is the result of boiling caused by applied heat or due to exothermic chemical reactions.
When a liquid reaches its boiling point there is a rapid escape of gas that is a result of the boiling. Boiling occurs when the vapor pressure within the liquid matches the pressure of the container and the atmosphere and the liquid vaporizes.
The rate of vaporization increases as the temperature increases.
When bubbles are observed, the process is referred to as nucleate boiling and each bubble is vaporized gas generated nearest the heat and then it rises to the surface.