( ( The ( limiting reagent ) ) ( ( must ( be ( ( identified ( in order ) ) ( to ( ( ( calculate ( ( the ( percentage yield ) ) ( of ( a reaction ) ) ) ) , ) ( since ( ( the ( theoretical yield ) ) ( is ( defined ( as ( ( ( the amount ) ( of product ) ) ( obtained ( when ( ( the ( limiting reagent ) ) ( reacts completely ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (JJ limiting) (NN reagent)) (VP (MD must) (VP (VB be) (VP (VBN identified) (PP (IN in) (NP (NN order))) (S (VP (TO to) (VP (VB calculate) (NP (NP (DT the) (NN percentage) (NN yield)) (PP (IN of) (NP (DT a) (NN reaction)))) (, ,) (SBAR (IN since) (S (NP (DT the) (JJ theoretical) (NN yield)) (VP (VBZ is) (VP (VBN defined) (SBAR (IN as) (S (NP (NP (DT the) (NN amount)) (PP (IN of) (NP (NN product)))) (VP (VBD obtained) (SBAR (WHADVP (WRB when)) (S (NP (DT the) (JJ limiting) (NN reagent)) (VP (VBZ reacts) (ADVP (RB completely)))))))))))))))))) (. .)))
The limiting reagent must be identified in order to calculate the percentage yield of a reaction, since the theoretical yield is defined as the amount of product obtained when the limiting reagent reacts completely.
(ROOT (S (NP (NP (DT The) (NN amount)) (PP (IN of) (NP (NP (NN product)) (SBAR (WHNP (WDT that)) (S (VP (MD may) (VP (VB be) (VP (VBN produced) (PP (IN by) (NP (DT a) (NN reaction))) (PP (IN under) (NP (VBN specified) (NNS conditions))))))))))) (VP (VBZ is) (VP (VBN called) (NP (JJ theoretical) (NN yield)))) (. .)))
The amount of product that may be produced by a reaction under specified conditions is called theoretical yield.