Lecture PowerPoints on Chapter 13 Physics PDF

**Lecture PowerPoints** ***Physics: Principles with*** ***Applications, 7^th^ edition*** Chapter 13 ========== Contents of Chapter 13 ---------------------- - Atomic Theory of Matter - Temperature and Thermometers - Thermal Equilibrium and the Zeroth Law of Thermodynamics - Thermal E...

**Lecture PowerPoints** ***Physics: Principles with*** ***Applications, 7^th^ edition*** Chapter 13 ========== Contents of Chapter 13 ---------------------- - Atomic Theory of Matter - Temperature and Thermometers - Thermal Equilibrium and the Zeroth Law of Thermodynamics - Thermal Expansion - The Gas Laws and Absolute Temperature - The Ideal Gas Law - Problem Solving with the Ideal Gas Law Contents of Chapter 13 ---------------------- - Ideal Gas Law in Terms of Molecules: Avogadro's Number - Kinetic Theory and the Molecular Interpretation of Temperature - Distribution of Molecular Speeds - Real Gases and Changes of Phase - Vapor Pressure and Humidity - Diffusion 13-1 Atomic Theory of Matter ---------------------------- 13-1 Atomic Theory of Matter ---------------------------- 13-3 Thermal Equilibrium and the Zeroth Law of Thermodynamics ------------------------------------------------------------- (13-1b) (13-2) Water behaves differently from most other solids---its minimum volume occurs when its temperature is 4°C. As it cools further, it expands, as anyone who has left a bottle in the freezer to cool and then forgets about it can testify. *PV* *mT* (13-3) 13-7 Problem Solving with the Ideal Gas Law ------------------------------------------- Useful facts and definitions: - Standard temperature and pressure (STP) T = 273 K (0°C) P = 1.00 atm = 1.013 × 10^5^ N/m^2^ = 101.3 kPa - Volume of 1 mol of an ideal gas is 22.4 L If the amount of gas does not change: - Always measure *T* in kelvins - *P* must be the absolute pressure 13-8 Ideal Gas Law in Terms of Molecules: Avogadro's Number ----------------------------------------------------------- 13-8 Ideal Gas Law in Terms of Molecules: Avogadro's Number ----------------------------------------------------------- (13-4) - large number of molecules, moving in random directions with a variety of speeds - molecules are far apart, on average - molecules obey laws of classical mechanics and interact only when colliding - collisions are perfectly elastic (13-6) (13-8) (13-9) 13-10 Distribution of Molecular Speeds -------------------------------------- An open container of water can evaporate, rather than boil, away. The fastest molecules are escaping from the water's surface, so evaporation is a cooling process as well. The inverse process is called condensation. When the evaporation and condensation processes are in equilibrium, the vapor just above the liquid is said to be saturated, and its pressure is the saturated vapor pressure. The saturated vapor pressure increases with temperature. (13-10) - All matter is made of atoms. - Atomic and molecular masses are measured in atomic mass units, u. - Temperature is a measure of how hot or cold something is, and is measured by thermometers. - There are three temperature scales in use: Celsius, Fahrenheit, and Kelvin. - When heated, a solid will get longer by a fraction given by the coefficient of linear expansion. - The fractional change in volume of gases, liquids, and solids is given by the coefficient of volume expansion. Ideal gas law: *PV* = *nRT* - One mole of a substance is the number of grams equal to the atomic or molecular mass. - Each mole contains Avogadro's number of atoms or molecules. - The average kinetic energy of molecules in a gas is proportional to the temperature: (13-8) Below the critical temperature, a gas can liquefy if the pressure is high enough. - At the triple point, all three phases are in equilibrium. - Evaporation occurs when the fastest moving molecules escape from the surface of a liquid. - Saturated vapor pressure occurs when the two phases are in equilibrium. - Relative humidity is the ratio of the actual vapor pressure to the saturated vapor pressure. - Diffusion is the process whereby the concentration of a substance becomes uniform.