[FlyMeToTheMoonDQ]

Can both liquid and steam exist at 100 degree C?


What must be changed-temperature or heat energy-during condensation?

[rudi_in]

Thank you for posting your question to the Ask Me Help Desk.

The short answer to this question is yes.

The boiling point of water is 100 degrees Celsius. At this temperature the water will begin to change from the liquid state to the gas state. In order for this change to take place, additional energy is required. In fact, every gram of liquid water requires 540 calories of heat energy just to convert it to steam. This is called the Heat of Vaporization. During the conversion process, temperature does not increase. It is, therefore, possible to have both liquid water and steam that exist at 100 degrees Celsius. While they both would exist at the same temperature, the steam would have a lot more heat energy due to the additional 540 calories per gram of heat energy that has been absorbed.

This is why steam burns are worse than the water burns.

The temperature of steam can continue to rise well above 100 degrees Celsius if it is contained and additional heat energy continues to be added but the water in liquid form will not go above 100 degrees as long as it does not have any impurities in it and assuming that standard pressure remains constant.

During condensation heat energy is released. It will be good to note, however, that even now as I type this and it is 19 °F that there is water vapor in the air. Condensation will not take place but rather deposition will and the heat energy will still be released.

In fact, this latent heat is a major player in the Earth/Atmosphere system.