It is well known that the temperature at which water freezes to ice or boils at a pressure of 1 atm, are 0°C and 100°C. In the next two tasks, we will now investigate what the temperatures would be at the top of Mount Everest, where the pressure is only 0.337 bar. The standard molar enthalpy of fusion of water at 0°C is ΔfusHmo = 6.008 kJ mol-1 and the standard molar enthalpy of vaporization of water at 100°C is ΔvapHmo = 40.656 kJ mol-1. The density of liquid water at 0°C is ρ(l) = 999.9 kg m-3, while the density of ice at 0°C is only ρ(s) = 916.2 kg m-3. The densities and enthalpies are assumed to be independent of temperature. 1) Calculate the temperature at which ice melts on top of Mount Everest. 2) Calculate the temperature at which water boils on top of Mount Everest.

It is well known that the temperature at which water freezes to ice or boils at a pressure of 1 atm, are 0°C and 100°C. In the next two tasks, we will now investigate what the temperatures would be at the top of Mount Everest, where the pressure is only 0.337 bar. The standard molar enthalpy of fusion of water at 0°C is ΔfusHmo = 6.008 kJ mol-1 and the standard molar enthalpy of vaporization of water at 100°C is ΔvapHmo = 40.656 kJ mol-1. The density of liquid water at 0°C is ρ(l) = 999.9 kg m-3, while the density of ice at 0°C is only ρ(s) = 916.2 kg m-3. The densities and enthalpies are assumed to be independent of temperature. 1) Calculate the temperature at which ice melts on top of Mount Everest. 2) Calculate the temperature at which water boils on top of Mount Everest.

Chemistry: Matter and Change

1st Edition

ISBN:9780078746376

Author:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl Wistrom

Publisher:Dinah Zike, Laurel Dingrando, Nicholas Hainen, Cheryl Wistrom

Chapter15: Energy And Chemical Change

Section: Chapter Questions

Problem 80A

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