The Science of Boiling Water: Beyond 100 Degrees Celsius

About water boiling, there is a common notion that water boils at 100 degrees Celsius (212 degrees Fahrenheit) under standard atmospheric conditions. While this is true for everyday purposes, the reality gets more fascinating when pressure comes into play. In this article, we'll explore the concept of boiling water at temperatures higher than 100 degrees Celsius, and even learn about a fascinating demonstration involving water at its freezing point.

Boiling Point of Water at 190 Degrees Celsius

No, water cannot be boiled at 190 degrees Celsius under normal atmospheric pressure. The boiling point of water is 100 degrees Celsius at sea level with 1 atmosphere of pressure, which translates to 212 degrees Fahrenheit. However, by increasing the pressure, you can indeed raise the boiling point of water. This is why pressure cookers can reach temperatures above 100 degrees Celsius. For instance, in a pressure cooker, the boiling point of water can exceed 100 degrees Celsius due to the high pressure inside the cooker. Achieving boiling at 190 degrees Celsius would require a significant increase in pressure, typically seen in industrial applications or specialized equipment.

Effect of Pressure on Boiling Temperature

Adjusting the pressure on water can push its boiling point from 32 F (0 degrees Celsius) to any higher temperature theoretically. This is because pressure and temperature are inversely related: the lower the pressure, the lower the boiling point, and vice versa. However, this principle doesn't apply once water transitions to its solid state (ice) at 32 degrees Fahrenheit.

A demonstration to show this can be performed in a laboratory using a vacuum pump. By reducing the pressure on water at 32 F, it can be forced to boil at 33 F. To understand the science behind this, one must delve into the pressure-temperature relationship and the properties of water.

Pressure Cooker Operation

One practical way to achieve a higher boiling point of water is by using a pressure cooker. Pressure cookers work by increasing the pressure inside the cooker, which raises the boiling point of water. By maintaining a higher pressure, a pressure cooker can reach temperatures above 100 degrees Celsius, which is faster and more efficient for cooking foods.

Steam Tables and Temperature-Pressure Relationship

For those curious about the specific relationship between temperature and pressure in water, steam tables can provide detailed information. Steam tables are tables that list the properties of water and steam at different temperatures and pressures. For example, at 12 atmospheres of pressure, the boiling point of water shifts significantly. Detailed steam tables such as the Saturated Steam Table by Temperature are available in scientific literature and online resources, offering a comprehensive view of how pressure impacts the boiling point of water.

In summary, while 100 degrees Celsius (212 degrees Fahrenheit) is the boiling point of water at standard atmospheric pressure, adjusting the pressure can indeed raise this temperature. This is achieved through the use of pressure cookers, and understanding the principles behind the pressure-temperature relationship in water is key to grasping this fascinating phenomenon.