You want to explore the feasibility of cooling 10 grams of computer chips that are initially...

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You want to explore the feasibility of cooling 10 grams of computer chips that are initially at 20°C and occupy an approximate volume equal to 2 cm³ by placing them in a saturated liquid bath of R-134a. You look around in the lab and find a well-insulated small cubic container of internal dimensions 3 by 3 by 3 cm., sufficient to place the 10 grams of chips and submerge them completely in R-134a at -40°C such that their final temperature of the chips results equal to -40°C. Assuming that the pressure in the R-134a remains constant while the chips are being cooled, the container is adiabatic and has no mass leaving to the surroundings, and the specific heat of the chips is equal to 0.3 kJ/kg-K, determine the following. a. The entropy change of the chips, in kJ/K. b. The entropy change for the R-134a, in kJ/K. Hint: you will need to determine the mass of liquid R-134a that will be needed to fill the container when the chips are inside and the amount of mass that may get vaporized as a result of the heat transfer from the chips to the R-134a. Pay attention to the assumption mentioned above. C. The entropy change for the entire system and the entropy generated, in kJ/K d. Is this cooling process possible? Why? Justify your answer with computations. You want to explore the feasibility of cooling 10 grams of computer chips that are initially at 20°C and occupy an approximate volume equal to 2 cm³ by placing them in a saturated liquid bath of R-134a. You look around in the lab and find a well-insulated small cubic container of internal dimensions 3 by 3 by 3 cm., sufficient to place the 10 grams of chips and submerge them completely in R-134a at -40°C such that their final temperature of the chips results equal to -40°C. Assuming that the pressure in the R-134a remains constant while the chips are being cooled, the container is adiabatic and has no mass leaving to the surroundings, and the specific heat of the chips is equal to 0.3 kJ/kg-K, determine the following. a. The entropy change of the chips, in kJ/K. b. The entropy change for the R-134a, in kJ/K. Hint: you will need to determine the mass of liquid R-134a that will be needed to fill the container when the chips are inside and the amount of mass that may get vaporized as a result of the heat transfer from the chips to the R-134a. Pay attention to the assumption mentioned above. C. The entropy change for the entire system and the entropy generated, in kJ/K d. Is this cooling process possible? Why? Justify your answer with computations.

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To determine the entropy change of the chips we can use the equation S mc lnTfTi where S is the entropy change mc is the mass of the chips Tf is the f... View the full answer