At sea level, water boils at 100° Celsius. Why can't boiling water get any hotter than this?

Question

At sea level, water boils at 100° Celsius. Why can't boiling water get any hotter than this?

Group of answer choices

The process of boiling cools the water as fast as it is heated up

The Celsius scale stops at 100

Once water reaches 100° its molecules stop moving

The gas bubbles created by boiling absorb excess temperature

Answer 1

So maybe the question here is really, "what is boiling?"

Well, obviously it's going from liquid to gas, but there's more to it. When objects are in the liquid state, the particles inside (water molecules, in this case), are bouncing around into each other. When you add heat to this liquid, the particles start bouncing faster and faster, which creates an outward pressure. This is why liquids and gasses expand when heated.

Now, what keeps water from boiling is that there is a pressure from the air that counteracts that outward pressure resulting from the water's heat. So, if you have a tea kettle, this water is trying to expand, but on most sides, the tea kettle is holding it in, and on the top, the air is pushing down, so it's being pushed in from all sides. If you add enough heat though, the internal pressure in the hot water will overpower the external air pressure. Some particles will evaporate into hot steam, which releases some of that internal pressure and keeps the balance with the air.

Where I live in Colorado, air pressure is noticeably lower than down at sea level. For this reason, water actually boils below 100^o Celsius, since the air isn't pushing down as hard on us. So logically, without any pressure at all (like in space), there would be no water at all - it would all be in gaseous form.