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In this problem on the topic of entropy, we have a block of tungsten that has a mass of 45 grams at a temperature of 30 degrees celsius and a block of silver with mass 25 grams at a temperature of minus 120 degrees celsius that are placed together in an insulated container.
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We want to find the equilibrium temperature as well as the entropy changes that the tungsten, silver and the system undergo in reaching the equilibrium temperature.
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Now, starting from the net heat in the system equal to zero from calorimetry, we can derive that the final temperature, tf, is equal to the heat capacity of one material times the mass of that material, times its temperature t1, that's the same for the other material, c2, m2, to t2 divided by the specific heat capacity c1 times m1 plus c2 times m2.
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And since we have all of these values, we get the final temperature to be minus 44 .2 degrees celsius, which is equivalent to 229 kelvin.
01:31
Next, for part b, since we have the equilibrium.
01:39
Temperature, we can find the change in the entropy of the tungsten firstly, delta s for tungsten is the integral from 3 or 3 to 229 of cmd over t, which is 134 into 0 .045 ,000...