Stoichiometry 1 Literally means ?to measure the elements? Answers questions like?How much is needed?? and ?How much is produced?? Stoichiometry Unit analysis 365 days 1 year 24 hrs 1 day 3600 sec. 1 hr 1 year How many seconds are in a year? = 31,536,000 sec. Unit analysis We use unit analysis in stoichiometric problems also. Grams-to-moles conversion factors are found in the periodic table. Unit analysis Mole-to-mole conversion factors are found in the coefficients of the equation. A mole-to-mole conversion changes moles of one substance to moles of another substance. ?Skeleton Equation?