Calculating Boiler Capacity and Steam Properties

AI Thread Summary
To calculate the water needed to fill a 5.0 m^3 boiler with steam at 50 atm and 400 degrees Celsius, it's essential to use steam tables to find the specific volume of superheated steam rather than the ideal gas law. Once the specific volume is determined, the mass of the water vapor can be calculated, which can then be converted to the volume of liquid water using its density. For the steam exiting the turbine at 2.0 atm and 150 degrees Celsius, the new volume can also be found using steam tables to determine the specific volume at those conditions. The discussion emphasizes the importance of using steam tables for accurate calculations in thermodynamic scenarios involving steam. Accurate calculations are crucial for efficient boiler operation and energy generation.
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Homework Statement


An electric generating plant boils water to produce high pressure steam. The steam spins a turbine that is connected to the generator.
a) how many liters of water must be boiled to fill a 5.0 m^3 boiler with steam at 50 atm and 400 degrees Celsius.
b) The steam has dropped to 2.0 atm at 150 degrees Celsius as it exits the turbine. How much volume does it now occupy?


Homework Equations


pv=nRT (not sure...but think you have to use some sort of ideal gas equation)


The Attempt at a Solution


Can you somehow find moles of the steam and then convert that to the liquid state somehow... do you use stochiometry?
 
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I'd assume an ideal gas unless you've been told to do otherwise.

If you can calculate the number of moles of water you need, then you can calculate the mass of water you need. Then just look up the density of water to get the volume.
 
Do not use the ideal gas law. You are dealing with superheated water vapor. Use steam tables and find the specific volume of the steam at the indicated pressure and temperature. Since you know the volume you can determine the mass of the water vapor.
 
My advice would be to follow RTW69's advice, not mine.
 
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