NEWTON:Heat Capacity Air and Humidity

 Heat Capacity Air and Humidity ``` Name: Sarah Status: student Grade: 9-12 Country: Canada Country: India Date: Spummer 2014 ``` Question: This question is very complex. Several parameters have to be taken into account, depending upon what it is you want to know. Here are some of the parameters: 1. What is the temperature ? 2. What is the pressure? 3. What is the water content of the air in question? 4. Is the heat capacity measured at constant pressure, volume, or temperature? This is a multivariable problem that does not converge onto a single solution. Replies: Hi Sarah, Highly simplified, moist air. Let us assume you are thinking about isobaric heat capacity measured in Joules per gram-Kelvin. We find that dry air, 273K, at sea level is 1.0035 J/gmK. For an altitude of 194 meters above sea level (an average for humans), an indoor temperature of 23°C, a dew point of 9°C and 760 mm–Hg sea level, we get 11.012 J/gmK. For steam, we see 2.08 J/gmK. The reason : Water has a huge heat capacity. Pervasive H bonding allows vibratory motions and bond length stretching to buffer changes in temperature. Peter E. Hughes, Ph.D. Milford, NH Click here to return to the Weather Archives

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