Why water is not used in the column to measure high pressure?

Water is not typically used in high-pressure columns because it has a relatively low boiling point and can easily vaporize under high pressure conditions. This can lead to inaccuracies in the measurement of pressure and can also pose safety risks. Additionally, water is not as stable or inert as other fluids commonly used in high-pressure applications, such as oils or gases. These fluids are better suited for maintaining accurate and reliable pressure measurements in high-pressure columns.

Water is not used in the column to measure high pressure because it has a low boiling point. At high pressures, the boiling point of water increases, and the water would vaporize and turn into steam. This would make it difficult to accurately measure the pressure.

Instead, mercury is used in the column to measure high pressure. Mercury's boiling point is much higher than that of water, so it does not vaporize at high pressures. This makes it a more accurate way to measure high pressure.