How much heat is lost when 0.10kg of steam at 100 °C condenses to water at 80 °C?

Answer is about 240000, but I don't know how to get that. Help is appreciated :)

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  • 1 year ago
    Favorite Answer

    Start with energy required to boil water

    (enthalpy of vaporization ≈ 2.257 MJ/kg)

    .1kg × 2.257MJ/kg = .2257MJ = 225.7kJ

    Find water's specific heat: ≈ 4.186kJ/kgC

    Q = specific heat × mass × dT

    Q = 4.186kJ/kgC × .1kg × 20C = 8.372 kJ

    225.7 + 8.372 ≈ 234.072 kJ

  • 1 year ago

    around 234J

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  • 1 year ago

    1 find the latent heat of vapourization for water. (A) 2256.4 kJ / kg = 2.2564*10^6 J/kg

    2. find the specific heat of water. (B) 4200 J/K / kg

    Note that the loss of temperature after condensing is 20 K ( Celsius)

    the lost heat is mass *(A + 20B) = 0.10 *(2.2564*10^6 + 20 * 4200) = 2.34 * 10 ^ 5 J

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  • Enigma
    Lv 6
    1 year ago

    20%

    • Lol I guess that is technically correct xD

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