Page 174 - Chemistry eBook
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Heat of Vapor Equation
How to Solve Heat of Vapor Equations (boiling and condensing)
Non-Regents Question: How much heat is released when 70 grams of water condense? Reffy: Table T (p. 12)
1. Since the question asks how much heat is released when water condenses, we know that we need the heat of vaporization value. (Hv = 2260 J)
2. Since we need to figure out the heat of vapor for 70 grams, we need the equation that includes mass: .
3. Let’s plug the values into the equation: heat = 70 grams (mass)× 2260 (Hv) 4. Calculate: q = 70 × 2260 = 158,200 joules
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