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**1. Homework Statement**

a 1kg of Water at 25 degrees celsius is in a container. A solid block of 1kg Carbon Dioxide at its sublimation temp of -80 degrees celcious is placed into the container, with the lid then closed.

Final temperature of entire system = 0 degrees celcius

Final phase of the Carbon Dioxide is gas

*What is the final mass of the liquid H20, solid H20, and gaseous H20?

**2. Homework Equations**

Heat of Vap of Water = 2000 kj/kg

Heat of Melt of Water = 300 kj/kg

Csp of Water = 4 kj/kg

Csp of CO2 gas = 1 kj/kg

Heat of Sub of CO2 = 200 kj/kg

[delta]Ethermal = mc[delta]T

[delta]Ebond = ([delta]m)([delta]Heat of...)

**3. The Attempt at a Solution**

From what I understand, the H20's conditions change as follows:

Temp Initial = 25 degrees celcius

Temp Final = 0 degrees celcious

Phase Initial = Liquid

Phase Final = Solid

Thus, the H20 will have its thermal energy increasing and its bond energy increasing as well.

As for the CO2's conditions:

Temp Initial = -80 degrees celcius

Temp Final = 0 degrees celcius

Phase Intial = Solid

Phase Final = Gas

Since it is at it's sublimation temperature, it will skip over its intermediate state as a liquid and its thermal energy is increasing and its bond energy decreasing.

So, to find the

**final mass of the liquid water**, do I just use:

[delta]Ethermal = Q

mc[delta]t = Q

(1kg)(4kj/kg K)(0celcius-25celcius) = Q

-100 kj = Q

[delta]m = Q/[delta]Heat of...

[delta]m = -100/300 kg/kg <-- do I use Heat of melting for the liquid phase?

What should be the next step I take in finding the mass of solid water and gaseous water?