Isobaric heating to find volume and temperature

[marcas3]

Homework Statement

Initially, 2 kg of water is at 250 Celsius and it exists as a saturated liquid. It is now isobarically heated until all of it is converted to saturated vapor. Find final temperature and volume.

Homework Equations

Thermodynamic tables and the use of interpolation.

The Attempt at a Solution

Since the process is isobaric, it is heated at a constant pressure. Next, using thermodynamic tables, the specific volume of the saturated liquid (v_f) is .001252 m^3/kg and the initial pressure is 3976.2 kPa at 250 Celsius. To find actual initial volume we just divide the specific volume by the mass (2 kg).

Trouble I am having is finding the final temperature and final specific volume (now I am looking for v_g since the water now exists as a saturated vapor). I thought about using the pressure table to find v_g and temperature but this doesn't make sense to me because then it seems the final temperature would be the same as the initial temperature, which I don't think is possible since this process is not isothermal. Please help.

 

[Borek]

As long as there is water present (and pressure is constant) process is also isothermic - temperature will go up once there will be no water to boil up and consume added heat.

Name 'latent heat' didn't came from nowhere.