What could cause a less than 100% yield? a. not letting the reaction run long enough and heating the flask b. letting the reaction run too long and cooling the flask c. chemical contaminants and too much reaction time d. chemical contaminants and too little reaction time submit for grading save and finish later?

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).