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Homework Help: Entropy, probably easy

  1. Sep 21, 2008 #1
    1. The problem statement, all variables and given/known data
    In making raspberry jelly, 952 g of raspberry juice is combined with 930 g of sugar. The mixture starts at room temperature, 23.0°C, and is slowly heated on a stove until it reaches 220°F. It is then poured into heated jars and allowed to cool. Assume that the juice has the same specific heat as water. The specific heat of sucrose is 0.299 cal/g·°C. Consider the heating process.

    (b) How much energy does the mixture absorb?
    (c) What is the minimum change in entropy of the jelly while it is heated?
    3. The attempt at a solution

    I have calculated part b, but I can't figure out how to do part c. For part b I got an answer of 4.19 x 10^5 J.

    I just can't figure out what to do for part C. Since it absorbs 4.19 x 10^5 J I did Q/T, but that is wrong. Any help would be nice, thanks.
  2. jcsd
  3. Sep 22, 2008 #2
    Would I find the entropy by using m*c*ln(Tf/Ti) for both of the materials and then adding that together?
  4. Sep 22, 2008 #3
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