I am looking for help with the following question please.
A piston cylinder device contains 28g of saturated water vapor that is maintained at a constant pressure of 300 kPa. A resistance heater within the cylinder heats the saturated water by added 8 kJ of heat. At the same time, a heat loss of 3.5 kJ occurs.
(i) Show that for a closed system the boundary work Wb and change in internal energy $\Delta U$ in the first law relation can be combined into one term, $\Delta H$, for a constant
(ii) Determine the final temperature of the steam.
So far i have this for (i):
For a constant pressure expansion or compression process:
$$\delta u + Wb = \delta H$$
which is a quasi equilibrium process
I am quite stuck on this. I would like some pointers to start through this please. I'm looking to understand the problem better.
For (ii) i have found how to complete the question. Now could i get some help to complete the question please? How do i calculate State 1 to get 2724.9 kJ/Kg??
Once i keno this then i can place my information in and calculate the final temperature of the steam.