When boiling water, what is the degree of freedom inside the vapour dome?

• Death eater
In summary, the conversation discusses the formation of a vapour dome when converting water to steam through boiling. The topic of the degree of freedom inside the vapour dome and on the saturated points is brought up, and the question of whether the phase rule applies to this situation is raised. The conversation then delves into the concept of degree of freedom being 1 in the wet region, and the use of the Gibbs formula to determine this value. The importance of knowing two properties, such as pressure and dryness fraction, to locate a point inside the dome is also mentioned. The conversation ends by clarifying that there is only one component involved and the discussion is about the equilibrium state.

Death eater

When water converts to steam while boiling a vapour dome can be formed, what is the degree of freedom inside this vapour dome and on the saturated points?

Bystander said:
Actually I wanted to understand why degree of freedom is 1 in the wet region ??
I know by the Gibbs formula it comes 1 but to locate certain point inside the dome we need to know two properties ( eg- pressure and dryness fraction) ?
How can we define the state by just one intensive property?

Death eater said:
dryness fraction
How many components?

Bystander said:
How many components?
There is only 1 component

Death eater said:
only 1 component
At equilibrium?

1. What is the vapour dome in boiling water?

The vapour dome is the region in a phase diagram where both liquid and vapor phases coexist at equilibrium. It is the curved boundary between the liquid and vapor regions.

2. What determines the degree of freedom inside the vapour dome?

The degree of freedom inside the vapour dome is determined by the temperature and pressure of the system. These two variables are closely related and affect the phase transition between liquid and vapor.

3. How does the degree of freedom change when boiling water at different altitudes?

The degree of freedom inside the vapour dome will change at different altitudes due to the change in atmospheric pressure. As altitude increases, atmospheric pressure decreases, resulting in a lower boiling point for water and a wider vapour dome.

4. Can the degree of freedom inside the vapour dome be manipulated?

The degree of freedom inside the vapour dome can be manipulated by adjusting the temperature and pressure of the system. Changes in these variables can shift the phase equilibrium point and change the size and shape of the vapour dome.

5. What happens to the degree of freedom when water reaches its boiling point?

At the boiling point of water, the degree of freedom inside the vapour dome is one. This means that only one variable, either temperature or pressure, can be changed while maintaining equilibrium between the liquid and vapor phases. Any change in the other variable will result in a phase transition outside of the vapour dome.