!"# “AÑO DEL BUEN SERVICIO AL CIUDADANO”
UNIVERSIDAD NACIONAL DE INGENIERIA FACUL ACULTAD TAD DE INGENIERIA AMBIENTAL
4° INFORME DE LABORATORIO
VALORACIÓN DE ACIDOS Y BASES FISICOQUÍMICA
DOCENTE: YUPANQUI YUPANQUI PORRAS PORRAS BILMA INTEGRANTES: ALTAMIRANO RODRIGUEZ ISABEL CASTRO VELEZ JOSEPH DÁVILA DÁVILA MERINO VICTOR FELIX RAMIREZ JHONEL SAENZ SANCHEZ PATRICK
UNIVERSIDAD NACIONAL DE INGENIERIA FACUL ACULT TAD DE INGENIERIA AMBIENTAL
I.
; T < . = ÍNDICE , / $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ INTRODUCCIÓN$$$$$$$$$$$$$$$$$$$$$
II.
RESUMEN$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$ 6
II III. I. OBJETIVO IVOS$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$ $$$$$$$$ 5 % IV. IV. FUNDA FUNDAME MENT NTO O TEÓR TEÓRICO ICO$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ % V.
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$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ & MATERIALES$$$$$$$$$$$$$$$$$$$$$
VI. REACTIVOS$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$ ' VII. VII. TABLA ABLAS S$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$ + #
* VIII. CÁLCULOS, RESULTADOS RESULTADOS Y OBSERVACIONES OBSERVACIONES$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$( 1 1 X. DISCUSIONES$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$ * "4
IX. IX. PROC PROCED EDIM IMIE IENT NTO O$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$ "%
XI. CONC CONCLU LUS SIONE IONES S$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ "4
, "4 XII. XII. BIBL BIBLIO IOGR GRAF AFÍA ÍA$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$
* . XIV. XIV. ANEXOS ANEXOS$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ 5 "' $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ Nº CAS: 7647-01-0$$$$$$$$$$$$$$$$$$$$ 1 ") * , Tablas > XIII. CUESTIONARIO CUESTIONARIO$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$"& "&
; L * # T*+,* T*+,* "- D*./0 /1232*,50 65 ,* 578512592* I$$$$$$$$$$$$$$$$ I$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ 0 T*+,* T*+,* - D*./0 /1232*,50 65 ,* 578512592* II$$$$$$$$$$$$$$$ II$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ + ) * 1 1 * 0 , * . 5 1 * , 5 0 0 / 8:3$ " 8 5 1 ? 5 9
UNIVERSIDAD NACIONAL DE INGENIERIA FACULTAD DE INGENIERIA AMBIENTAL
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;;;15 T T T @ < < < * I. INTRODUCCIÓN ...19 === * El estudio del pH es una herramienta importante para poder determinar la naturaleza de ,, ,1las reacciones ue se den en un medio! El pH condicionar" las reacciones dependiendo del 8 // ran#o en el ue se encuentre! $os %alores del pH depender"n de las reacciones ue se/den
= 6 6 6. En la piel( por e)emplo( el pH es de *(* de media( este %alor se mantiene mediante las 55 / 5 interacciones sudor & la super+icie de la piel! ,ara poder mantener un correcto +uncionamiento 0 del te)ido epitelial( no de'e %ariar 'ruscamente el pH( pudindose hacer esto mediante el2 uso ,,,@ de de productos '"sicos! 8 *** El pH de un cuerpo de a#ua es un par"metro a considerar cuando ueremos determinar/la 1 Es especiaci.n u/mica & solu'ilidad de %arias su'stancias or#"nicas e inor#"nicas en a#ua! ++ + . un +actor a'i.tico ue re#ula procesos 'iol.#icos mediados por enzimas! * * ** ,ara el control de po'laciones micro'ianas( el pH es uno de los +actores ue determinan 111. la super%i%encia & la especie de las po'laciones ue %i%an en un medio! Se#n el %alor de111pH 5 eistente en el medio( los microor#anismos alcanzan o no sus puntos de crecimiento .ptimo! *** 0 Eisten microor#anismos alcal.+ilos capaces de so're%i%ir en medio con pH entre 2(* & 11(0( 6 as/ como eisten microor#anismo acid.+ilos e hiperacid.+ilas capaces de %i%ir entre 0(0 ,&,5 2(*! ,, $as ltimas pueden estar presentes en los rela%es mineros siendo indicadoras de *** . contaminaci.n de este tipo! ...5 7 En la industria( se emplea el pH como indicador de calidad( esto so're todo en plantas5de 55 . tratamiento de a#uas residuales! As/( mismo( estos %alores de pH son controlados en las 111/ industrias alimentarias las cuales con el +in de prolon#ar el tiempo de %ida til de sus
entre compuestos "cidos & '"sicos!
productos( controlan los %alores de pH para ue no alcancen el punto de acti%aci.n dependiendo de las 'acterias!
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;;;3 LLL1 *** 5 II. RESUMEN 0003 * El presente in+orme %ersa so're la eperiencia en el la'oratorio N!3 4 correspondiente a +++ 1 * * *2 aloraciones 5cido-ase! 111 1 ,ara realizar la parte eperimental se %alor. con NaH 8'ase +uerte9( un "cido +uerte118"cido ? * ** clorh/drico9 & un "cido d'il 8"cido actico9! El proceso de %aloraci.n se dio mediante el 00/ 0 a#re#ado sucesi%o de peueos %olmenes de 'ase con molaridad 0!1 a los "cidos 1 con @ un molaridad( tam'in( de 0!1! ;ediante la toma de datos correspondientes al pH con , , ,* pHmetro( se tomaron los mismos despus del %ertimiento de cada %olumen! Este proceso *** 9 tu%o como +inalidad la ta'ulaci.n de las cur%as de titulaci.n para cada "cido! ...2 555 1 1 1 III. OBJETIVOS *** , , ,*
UNIVERSIDAD NACIONAL DE INGENIERIA FACULTAD DE INGENIERIA AMBIENTAL
=eterminar el error cometido en los procesos de titulaci.n =i+erenciar entre punto +inal & punto de eui%alencia
9995 ...? *** 5 0001 5 888 *** 9 1112 *** *
1111 555 : @ @ @ 8 *** 2 IV. FUNDAMENTO TEÓRICO 1116 999* *** ! 1119 / en E$ pH es acr.nimo para potencial de hidr.#eno( e indica la concentraci.n del i.n hidronio 888 @ una soluci.n! El trmino pH epresa la intensidad de un "cido( dependiendo de su capacidad === / de disociaci.n( as/ como de su concentraci.n! ...8 El potencial Hidr.#eno 8pH9 es una +orma con%encional & mu& con%eniente de epresar////se#n 0001 una escala numrica adimensional( el #rado de acidez o 'asicidad de soluciones acuosas diluidas! Es en realidad una medida de la acti%idad de los iones hidr.#eno en una soluci.n 2 25 2 >p? electrol/tica! Aplicando una de+inici.n matem"tica se epresan los trminos con una letra @ @ @ 5 el minscula ue antepone al s/m'olo como >lo#aritmo ne#ati%o del s/m'olo?! =e esta manera 8 88 @ pH es el ne#ati%o del lo#aritmo de la concentraci.n molar de iones hidr.#eno! Ha& ue tener /// 8 en cuenta ue se tra'a)a con pH en lu#ar de pH@ de'ido a ue el i.n H@ es representado 111, .../ por H ! =e esta manera: *** +¿ +¿ ..= . ¿ 55 H 5 * ¿ 000 H 3 O =−log ¿ 8 pH =−log ¿ 666 1 55 $a +acilidad de tra'a)ar con esta de+inici.n radica en ue se #enera una escala m"s 5+"cil , ,/ de , %isualizar( de lo contrario se tra'a)ar/an con nmeros mu& peueos! ,or e)emplo(..3si se .1 dispone de una concentraci.n de 0!0000001 molesB$ de H ( es mucho m"s c.modo 5tra'a)ar 55 * con el lo#aritmo ne#ati%o ue %ale 7( ue con 0!0000001! $a medida de pH es mu& til para 777 @ medir la acidez o 'asicidad de una sustancia( el ran#o de pH se encuentra entre .0..*& 14! / Siendo la zona "cida la ue tiene %alores de pH menores a 7 8H D H- D9 & la zona//'"sica 9 2 la ue tiene %alores de pH ma&ores a 7 8H D F H- D9! Si el %alor de pH es 7( la soluci.n // / DG ser" neutra( lo ue si#ni+ica ue la concentraci.n de "cido es i#ual a la de 'ase 8H H- D9! CIAIN ro14 Jl K0*2 D! *** $ 33 3 P Val"#a$%&' 111/ 555 1 de El an"lisis %olumtrico o titulaci.n( es el proceso por el cual se determina la concentraci.n 333 , una sustancia 8analito9 presente en una soluci.n pro'lema( la cual #eneralmente se dispone *** / en un matraz Erlenme&er( mediante el a#re#ado #ota a #ota de una soluci.n %alorante 111 8titulante9 de concentraci.n conocida desde una 'ureta hasta ue( idealmente toda la 3 2 2 25 del sustancia ha&a reaccionado( o se a ue se ha&a a#re#ado una cantidad eui%alente titulante! Entonces conociendo el %olumen utilizado del titulante & mediante un c"lculo ? ? ? 5 $a esteuiomtrico se puede calcular la concentraci.n del compuesto pro'lema! /// determinaci.n del punto +inal de la titulaci.n( se detecta por el cam'io 'rusco de 1al#una 111 * propiedad del sistema reaccionante en el erlenme&er( estimado mediante un @ reacti%o @ @ , indicador( idealmente este cam'io de'er/a presentarse en el momento en ue se *** ha&a 9 9 90 8:3$ % 2 2 25 9 / *** , 666 / 222
UNIVERSIDAD NACIONAL DE INGENIERIA FACULTAD DE INGENIERIA AMBIENTAL
/// 5 *** ,,, 666 , 555 *
1118 555 a#re#ado una cantidad eui%alente del titulante a la de la sustancia 'uscada! El indicador * ? ? ? 1 del ele#ido depende de las sustancias a reaccionar( el tipo de reacci.n & las condiciones 55 5 . punto +inal! $as %aloraciones constitu&en un amplio & %alioso con)unto de procedimientos 1115 cuantitati%os ue se usan mucho en u/mica anal/tica! $os mtodos %olumtricos representan 555 uno de los tres tipos de %aloraci.n ue est"n 'asados en la medida de la cantidad de 2 reacti%o( de concentraci.n conocida ue consume el analito! $os otros dos tipos de %aloraci.n 999 2 2 2 son la %aloraci.n #ra%imtrica & la %aloraci.n coulom'imtrica! En las %aloraciones ** = se %olumtricas se determina el %olumen de una soluci.n de concentraci.n conocida( *ue 2 necesita para reaccionar( de +orma completa con el analito! Iodos los mtodos %olumtricos 1115 est"n 'asados en est"ndares primarios( compuesto cu&a composici.n u/mica & pureza se ::: 1 conocen eactamente! Lna soluci.n est"ndar es una soluci.n de reacti%o de concentraci.n 888 2 26 una conocida ue se usa para realizar an"lisis %olumtrico! El punto de eui%alencia 2de * 6 6 6 %aloraci.n se alcanza cuando la cantidad de %alorante aadida es u/micamente eui%alente ** * 6 a la cantidad de analito ue ha&! Este punto es te.rico & eperimentalmente no se puede 5 determinar! Se puede estimar o'ser%ando al#n cam'io +/sico ue acompae la condici.n 9991 de eui%alenciaM a este punto se lo llama: punto +inal! /// 5 @ @ @ 9 Clas%(%$a$%&' )* bas*s + $%)"s /// * su Ie.ricamente( los "cidos +uertes son los ue se ionizan completamente en el a#ua( 888 concentraci.n es i#ual a la concentraci.n de iones hidr.#eno a temperatura & presi.n /// 0 constantes! En su ma&or/a son inor#"nicos( tales como: "cido clorh/drico( "cido sul+rico( 111= "cido n/trico( "cido percl.rico! $as 'ases +uertes se disocian completamente en a#ua! 8Entre 5 ellas se encuentran: hidr.ido de sodio( hidr.ido de potasio e hidr.ido de calcio! $os55"cidos 5 1 d'iles se ionizan le%emente! $as disoluciones acuosas de stos "cidos contienen molculas 55 5 2 de "cido no ionizadas! Entre stos se encuentran el "cido +luorh/drico( el "cido actico( el @ @ @ / "cido car'.nico! $as 'ases d'iles tam'in se disocian le%emente & entre ellas encontramos 888 1 hidr.ido de amonio( hidracina! , , ,/ /// 2 === ? *** 5 1 888 2 111/ /// 1 333 6 1115 *** @ @ @ , *** * 999 2 2 28 : 3 $ $ $2 PPP /// * 111$ N , , ,/ /// 8:3$ 4 / 333 + 555 0 . 555 * 111
