eng Science and Education Publishing World Journal of Chemical Education 2375-1657 2017-01-21 5 1 1 8 10.12691/wjce-5-1-1 WJCE2017511 article Diego J. R. da Silva diegoraposo@hotmail.com 1 Departamento de Química Fundamental Universidade Federal de Pernambuco, Recife, Brazil A general formalism for defining and identifying limiting reagent in closed systems is proposed and it is correlated to usual definitions and identification methods. An alternative definition of limiting reagent is proposed, based on real situations after the reaction is complete. Useful equations relating the limiting reagent to products and excess reagents (if the limiting reagent is completely consumed or not) and to reaction yields are given and briefly applied. http://pubs.sciepub.com/wjce/5/1/1/wjce-5-1-1.pdf limiting reagent stoichiometry percent yield excess reagent