Question

Can water be made to boil without heating?

Answer 1

Hint: Boiling a liquid not only depends upon the heating but also depends on the pressure. These two effects can make a great impact on the boiling. If the pressure reduces the boiling can occur at low temperatures. If the pressure increases the boiling occurs at high temperature. The pressure cooker is working with this principle.

Complete step-by-step answer:
The boiling point of a liquid depends not only on the temperature but also the pressure. Pressure cookers are extensively used in cooking to raise the temperature level at which the liquids will boil. We are using a pressure cooker even for the boiling of water hot enough in high altitude areas due to low pressure.
Water will boil at $100{}^\circ C$ under normal atmospheric pressure. But in a pressure cooker, the water can’t boil even if it is reached $105{}^\circ C$. If the pressure is reduced, then water starts to boil. Boiling means separation of molecules of the liquid and becoming gas. So it has to break the attractive forces within the molecules and attain more kinetic energy. If we are adding heat to a substance, we are delivering kinetic energy to break the intermolecular attraction. If you are removing the pressure, then the external forces applying on the surface can be avoided. So it can easily boil. We can boil cold liquids within less time by reducing the pressure. The liquid will boil but it doesn’t have heat that we are experiencing daily during boiling. That’s why in hill areas, liquids boil more easily than the coastal areas. The people who live in hill areas will use pressure cookers extensively. Otherwise, they can’t cook hard materials. Since the water will boil at normal temperature.

Note: If you are approaching this question not in a scientific way, you will get the wrong answer. You should consider the case of a pressure cooker to understand this easily. If we are cooking hard things like peas, then normal boiling won’t make any difference. To cook it perfectly we have to keep those in a pressure cooker and boil it in high temperatures. It is assumed that in space if you open a water bottle, suddenly it will boil away. Since the external pressure is zero in the space. Although the boiled water will still be cold.