19. What is the distinction between gas and vapor?21. Why does a beaker of 40.0ºC water placed in a vacuum chamber start to boil as the chamber is evacuated (air is pumped out of the chamber)? At what pressure does the boiling begin? Would food cook any faster in such a beaker?
Problems & Exercises39. Some incandescent light bulbs are filled with argon gas. What is vrms for argon atoms near the filament, assuming their temperature is 2500 K?41. (A) what is the average kinetic energy in joules of hydrogen atoms on the 5500ºC surface of the Sun? (B) What is the average kinetic energy of helium atoms in a region of the solar corona where the temperature is 6.00×105 K?