Im having a hard time getting started with this question.

A vessel having a volume of 5m^3 contains .05m^3 of saturated liquid water and 4.95m^3 of saturated water vapor at ,1Mpa. Heat is transferred until the vessel is filled with saturated vapor. Find the heat transfer for this process.

I have no Idea where to start, all the examples in my book/notes give the temperature and the mass, so I dont know what equation to use =(

I was thinking about finding the work using the pressure and volume, and then using this equation to solve for heat transfer:

heat transfer - work = pe+ke+internal energy

but that seems too simple. am i on the right track with that?

Grüss Dich Wankel!

You seem to be confusing the heat capacity of water, which involves a change of temperature with water remaining liquid or gaseous, and the heat associated with a phase transition (=vaporization enthalpy).

You'll find this enthalpy (2250kJ/kg at 1bar +100°C) in table books and websites.
- It is often measured at constant pressure of 1 bar (~100kPa) so check you have it at 1MPa
- Then the pressure in your vessel will increase as you evaporate some liquid, so you've to figure out a combination of transformations (vaporize at constant P, then compress to original volume, but then cool down the vapour so it is saturated again) that gives you the initial and final states.

Not completely easy. But doable. Good luck!