8/17/2019 Standardization of NaOH Using a Primary Standard
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CHEMISTRY IA- UNIT 1STANDARDIZATION OF SODIUM HYDROXIDE USING A
PRIMARY STANDARD
In order to analye !n"no#n $on$entrat%on&' a &tandard
&ol!t%on %& needed to rea$t
#%t( t(e !n"no#n&) A &tandard &ol!t%on %& one %n
#(%$( t(e $on$entrat%on %& "no#n
a$$!rately) Standard &ol!t%on& *ay +e ,re,ared +y #e%(%n
or *ea&!r%n an
a$$!rate a*o!nt o. &!+&tan$e and d%&&ol/%n %t %n
a %/en /ol!*e o. #ater)
Standard &od%!* (ydro0%de &ol!t%on $annot +e ,re,ared +y
#e%(%n +e$a!&e t(e&ol%d %& (%(ly (yro&$o,%$ and
%& not &!$%ently ,!re to +e !&ed a& a ,r%*ary
&tandard) Ho#e/er' a &ol!t%on o. &od%!* (ydro0%de o.
a,,ro0%*ate *olar%ty $an +e
,re,ared and t(en &tandard%ed +y t%trat%on #%t( a ,r%*ary
&tandard o. "no# ,!r%ty)
In t(%& e0,er%*ent' ,ota&&%!* (ydroen &!l,(ate
%& !&ed a& t(e ,r%*ary &tandard
and %t %& t%trated #%t( a &ol!t%on o. &od%!*
(ydro0%de) T(e ,ota&&%!* (ydroen
&!l,(ate %& an a$%d%$ &tandard #(%$( %&
&ta+le' ,!re and d%&&ol/e& %n #ater to
,rod!$e+¿ K
¿%on& and
−¿ HSO
4
¿%on&) T(e
−¿ HSO
4
¿%on& $onta%n a$%d%$
+¿ H
¿%on&
#(%$( rea$t −¿OH ¿ %on& a$$ord%n to t(e e2!at%on
+elo#)
SO4(aq)2−¿
OH (aq)−¿
→H 2O(l)+¿
HSO4(aq)−¿ +¿¿
Apparatus and Materials
1) &ol%d ,ota&&%!* (ydroen&!l,(ate
3) NaOH o. a,,ro0%*ately 1M4) ,(enol,(t(ale%n %nd%$ator
5) 67$*8 +!rette6) T(ree 367$*8 $on$%al 9a&":) 36$*8
*ea&!r%n $yl%nder;)
