|MadSci Network: Chemistry|
weight is calculated in pounds in this case and that is the same unit which would be used for water or steam. All you need to convert is from pounds to kilogram( just for easiness) and using density of water to be about 1000 kg/m^3 you would estimate the number of gallons. You do not have to worry about whether the weight is given for steam or water. Both are the same. [Moderator's note: A US gallon of fresh water weighs 8.34 pounds at 4 degrees centigrade, while a UK imperial gallon of fresh water weighs 10 pounds at 62 degrees Fahrenheit. -- SM]
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