What Happens to Water when Heat of the Pressure does/not get Transferred into the Water

You have a finite quantity of water which you are able to compress in an apparatus. The apparatus is theoretical and cannot break, and the amount of pressure it can apply to the water is both uniform and unlimited. Additionally, the apparatus is both air tight and water tight.

Two answers are required. Describe what happens to the water under each of the following conditions:

(1) When the heat of the pressure does not get transferred into the water.

(2) When the heat of the pressure does get transferred into the water.

Hint: In either situation the water does not turn to ice. Due to hydrogen bonding, ice is lighter than water and takes up more space.

We’re given that: PV = nRT.

(1) Heat of the pressure does not get transferred into the water. To say, temperature (T) remains constant, and Volume (V) decreases with increase in Pressure (P).

Let’s increase the pressure indefinitely, but uniformly. If the temperature is right, it might never form ice – and what you’ve assumed would be absolutely correct. At some point, electrons in water are so squished, they’re forced onto a same quantum mechanical state. Now this runs against the exclusion principle (which states that no two fermions (like electron) may occupy identical quantum states), and to counter, the electrons ‘fight back’. The counter pressure they exert is also called electron degeneracy pressure.

Eventually, further increase in pressure causes the protons in the nucleus to hog electrons (electron capture) while converting to neutrons. So now you’re hanging around with a thick soup of neutrons, and the neutrons too exert neutron degeneracy pressure. Squish it further (beyond a certain limit, called the Schwarzschild Radius), you have a black hole – you know what that is.

Now the temperature of the black hole really depends only on the amount of water you start with, not on what the initial temperature was.

(2) When the heat of pressure transfers into the water, simple as it sounds, it heats up. How hot can it get? Oh, that gets me spinning. Some say around 10³², where the laws of physics we’re so familiar with, break down. Who knows, increasing it even further might get us right back to zero – minus zero.