PHY 182 1st Edition Lecture 8 Outline of Last Lecture I. Density of WaterII. High Specific Heat of WaterIII. Kinetic Theory of GasesOutline of Current Lecture I. Heat Capacity of GasesII. Heat Capacity of SolidsIII. Molecular SpeedsCurrent LectureHeat Capacity of Gases- Ktr=3/2 nRT- When temperature changes by a small amount, so does the translational kinetic energy.- The amount of heat transferred is equal to the change in translational kinetic energy (no work is done so all heat goes into changing Ktr.- For a constant volume process, Cv=3/2 R. This approximation is very accurate for monatomic gases. However it is less accurate for diatomic gases and much less accurate for polynomial gases.- Diatomic molecules can store energy as rotational kinetic energy (so not all the heat in the process goes into translational energy).- Equipartition of energy: each velocity component (linear or angular) has an average associated kinetic energy per molecule of ½kT. These velocity components are called"degrees of freedom".These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- A monatomic gas molecule has 3 degrees of freedom (only translational velocity). Its kinetic energy = 3/2 kT.- A diatomic gas molecule has 5 degrees of freedom (translational and rotational velocity). Its kinetic energy = 5/2 kTHeat Capacity of Solids- A molecule of an ideal monatomic solid has 6 degrees of freedom.- Kinetic energy = 3kT- Cv=3R, this is approximately equal to 24.9Molecular Speeds- All molecules within a substance have different speeds.- The speed that is normally calculated for a gas is the average of the speeds of all the molecules in the gas.- You can use the distribution function to find the specific speeds of individual
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