Problem 10: In some countries, liquid nitrogen 1s used on dairy trucks instead of mechanical refrigerators. A 3.00-hour delivery trip requires 175 L of liquid nitrogen, which has a density of 808 kg/m³. Part (a) Calculate the heat transfer, in kilocalories, necessary to evaporate this amount of liquid nitrogen and raise its temperature from its boiling point of -195.8 °C to 3.00°C. This value is the amount of cooling the liquid nitrogen supplies. The latent heat of vaporization for liquid nitrogen is Ly = 48.0 kcal/kg and the specific heat for gaseous nitrogen is 0.248 kcal/(kg-°C). Q = Part (b) What is this heat transfer, in kilowatt-hours? Part (c) For comparison, how much heat transfer, in kilocalories, would be needed to melt an identical mass of ice at 0°C? The latent heat of fusion for water is Lf= 79.8 kcal/kg.

Problem 10: In some countries, liquid nitrogen 1s used on dairy trucks instead of mechanical refrigerators. A 3.00-hour delivery trip requires 175 L of liquid nitrogen, which has a density of 808 kg/m³. Part (a) Calculate the heat transfer, in kilocalories, necessary to evaporate this amount of liquid nitrogen and raise its temperature from its boiling point of -195.8 °C to 3.00°C. This value is the amount of cooling the liquid nitrogen supplies. The latent heat of vaporization for liquid nitrogen is Ly = 48.0 kcal/kg and the specific heat for gaseous nitrogen is 0.248 kcal/(kg-°C). Q = Part (b) What is this heat transfer, in kilowatt-hours? Part (c) For comparison, how much heat transfer, in kilocalories, would be needed to melt an identical mass of ice at 0°C? The latent heat of fusion for water is Lf= 79.8 kcal/kg.

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter21: The Kinetic Theory Of Gases

Section: Chapter Questions

Problem 21.25P

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