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Heat energy and Mass

  1. May 11, 2005 #1
    how can 30,000 kg of snow at 0 C have more heat energy than 1 mL of water at 100 C?
  2. jcsd
  3. May 11, 2005 #2


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    Staff: Mentor

    Snow at 0C still contains heat - more heat than snow at -5C. Heat content is measured on an absolute scale starting at absolute zero (-273C).
  4. May 12, 2005 #3


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    Staff Emeritus
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    Keep in mind that when measuring heat content, temperature must be measured on the Kelvin scale.
  5. May 12, 2005 #4
    Suppose we have a sample A of 30000 kg of ice and a sample B of 1g of ice(1ml of water) both at absolute zero, then if we start heating them, so that sample A reaches [tex] 0^{0}\ C[/tex] and sample B reaches [tex] 100^{0}\ C[/tex], we can calculate the heat they will have,

    [tex] \mbox{For Ice at sample A,}[/tex]

    [tex] M_{ice}\ S_{ice}\ (\delta T)\\ =\ 30000\times 1000 g\ (0.50 \frac{cal}{g K})\ (273.15\ K)[/tex]

    [tex]= 4097250000\ cal[/tex]

    [tex]= 9.788 \times 10^{5} kJ[/tex]

    [tex]\mbox{And for ice(water) at sample B,}[/tex]

    [tex] M_{ice B}\ S_{ice}\ (\delta T_{1})\ +\ M_{ice B}\ L_{fusion}\ +\ M_{water}\ S_{water}\ (\delta T_{2})[/tex]

    [tex]=\ 1g\ (0.50 \frac{cal}{g K})\ (273.15\ K)\ +\ 1 g\ (80\frac{cal}{g})\ +\ 1\ g\ (1\frac{cal}{g K})\ (100 K)[/tex]

    [tex]=\ 316.575 cal[/tex]

    [tex]=\ 7.562 10^{-2}\ kJ [/tex]

    So u can see, that the sample A of ice has much much more heat!! :approve:
    Last edited: May 12, 2005
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