Water, otherwise known as H20 on the periodic table, is maybe the most essential compound to human life. Humans, as well as most other forms of life, could not exist without water. It has unique characteristics that sets it apart from other forms of matter of the same compound. It is really the only compound that can be found in every single state of matter(gas, liquid, solid) at NORMAL temperatures on Earth.
First, it is the most dense state of matter out of liquid, solid, and gas. It is unusual that water has a higher density than a solid. This is why ice floats in water. This density means that water is not easily compressible. You have to remember that when the temperature increases, so does the volume. These two are directly proportional thanks to the universal gas law which is PV=nRT.
Second, water has hydrogen bonds in it. These covalent bonds are extremely strong because the intermolecular bonds share particles. This bond is very difficult to separate. It takes a lot of energy to break this bond. Temperature is measured by how fast molecules are moving around and giving off energy.
Thirdly, water has a really high specific heat. This means it can take a lot of heat before getting hot. This characteristic is more commonly known as conductibility. The same reason water can not be quickly heated is the same reason electricity passes through water very quickly.
Of course there is another important reason that water’s boiling point is at 100 degrees Celcius. It is because the celcius system is based on water. For example, 0 degrees celcius is the freezing point of water. Likewise, 100 degrees celcius is the boiling point of water. This proves the point that water is possibly the most important element to sustain human life on Earth.
Water’s boiling point is at 100 degrees Celcius ONLY if the pressure is at its standard point. The standard point of pressure is one atmosphere or 101.325 kilo pascals. Because of this relationship, the boiling point of water at the summit of a tall mountain is significantly lower than the boiling point of water at sea level. This can be explained by the universal gas law. Because PV=nRT,the pressure and temperature are directly proportional. If one goes up, the other must go up as well.
All of these different points that I have just made summarize the different reason that water’s boiling point is at 100 degrees Celcius.