Question: (a) At what depth in freshwater is the critical pressure of water reached, given that the surface is at sea level? (b) At what temperature will this water boil? (c) Is a significantly higher temperature needed to boil water at a greater depth?
Here, the surface is at sea level. So, the critical pressure has a contribution from the pressure of air and the pressure of water. The critical pressure of water is the pressure at its critical point. Its value is 22.12 x 106 Pa. To calculate the depth, first, we need to calculate the pressure of the water.
The pressure of air is the atmospheric pressure. Its value is 1.013×105 Pa. So, we know the pressure of air and the critical pressure. The pressure of water can be calculated by subtracting the pressure of air from the critical pressure.
Therefore, the pressure of water is 22.02×106 Pa. The pressure of water and its depth are related as follows;
Here is the pressure, the density, and the acceleration due to gravity. The density of water is 1000 Kg/m3, and the acceleration due to gravity is 9.8 m/s2. Substitute these values and calculate the depth.
Therefore, the depth of water is 22.469 m.
The boiling point is the temperature at which vapor pressure becomes equal to atmospheric pressure. Since the vapor pressure of water and the critical are almost equal, the temperature that corresponds to the critical pressure is the boiling point. That means the boiling point is equal to the critical temperature. So, the boiling point is 374.3°C.
A high temperature is required to boil water at a high depth because pressure increases with depth. The boiling point is the temperature at which the vapor pressure and the surrounding pressure become equal. The temperature rises in direct proportion to the pressure. So, at a higher depth, the temperature will be higher.
Thus, the depth of water is calculated as 22.469 m. The boiling point of water is 374.3°C. Temperature increase with altitude due to high pressure.
Question: (a) The density of water at 0ºC is very nearly (it is actually ), whereas the density of ice at 0ºC is . Calculate the pressure necessary to keep ice from expanding when it freezes, neglecting the effect such a large pressure would have on the freezing temperature. (This problem gives you only an indication of how large the forces associated with freezing water might be.) (b) What are the implications of this result for biological cells that are frozen?
94% of StudySmarter users get better grades.Sign up for free