# Microwaved Superheated Water

1. Nov 15, 2007

### Razorback

1. The problem statement, all variables and given/known data
1 Liter of water is microwaved to 103 Celcius at 1atm atmospheric pressure.
1)How much energy is released when you add a nucleation site to the container to release steam?Heat capacity of liquid water is 4.184 J/K*g
2)Ignoring surface tension, how much steam in mL could be produced given the latent heat of boiling water is 2260 J/g?

2. Relevant equations
H=U+PV
U=[Cv]Delta[T]

3. The attempt at a solution

U=[Cv]Delta[T]
U=(4.184 J/K*g)(3 K)
U=12.552 J/g

or

U=H-PV H(.1 MPa, 103 C)=2676.2 kJ/kg
U=(2676.2)-(.1 MPa)([10 [m]^{3}) steam tables and converting atm to MPa
U=2675.2 kJ/kg

As far as part 2 goes, I really need some help.

2. Nov 18, 2007

### Astronuc

Staff Emeritus
Convert the liter of water to a mass and determine the number of moles. One can find the volume of steam using the ideal gas - 1 mole of gas occupies 22.4 l of volume.

Otherwise use a steam table and select the appropriate specific volume for steam at 1 atm and 103C (slightly superheated), and multiply by the mass.