During an experiment, solid iodine was placed in a sealed container. the container was gradually heated and purple-colored vapors of iodine formed were observed. describe this system when it reaches phase equilibrium.

Butane gas reacts with oxygen gas to give carbon dioxide gas and water vapor (gas). if you mix butane and oxygen in the correct stoichiometric ratio, and if the total pressure of the mixture is 390 mmhg, what is the pressure (in mmhg) of water vapor after the reaction is completed (temperature and volume do not change).