Determination of total alkalinity of water sample

GC woman university sialkot

Lab report………1

Subject : Applied chemistry Submitted to: M’am Anum noor  Submitted by:  

Shaherbano Roll no:

 

(58)

Purpose:

To determine determine the alkalinity o !ater sample as tap !ater and distilled !ater by titration" Theory: (intro) Alkalinity is the name ame #i$en to the %ua %uantitati$e capa apacity city o an a%ueous a%ueous solution  solution to neutrali&e neutrali&e an  an acid acid"" Measurin# alkalinity is important in determinin# a stream's ability to neutrali&e acidic pollution rom rainall rainall or  or !aste!ater " t is one o the best measures o the sensiti$ity o the stream to acid inputs" There can be lon#term chan#es in the alkalinity o  streams and ri$ers in response to human disturbances" Alkalinity is related to the p* the p* o  o a solution (its basicity (its basicity)+ )+ but measures a dierent property" Rou#hly+ the alkalinity o a solution is a measure o ho! ,stron#, the bases are in a solution+ !hereas the p* measures the ,amount, o chemical bases" A #ood e-ample is a buer a buer solution solution++ !hich can ha$e many a$ailable bases (hi#h alkalinity) despite ha$in# onl y a moderate p* le$el.

Alkalinity measurements are used in the interpretation and control o !ater and !aste!ater  treatment processes" Ra! domestic !aste!ater has an alkalinity less than+ or only sli#htly #reater than+ that o the !ater supply" .roperly operatin# anaerobic di#esters typically ha$e supernatant alkalinities in the ran#e o /000 to 1000 m# calcium carbonate (2a234)6" Alkalinity is the measure o the resistance o !ater to the lo!erin# o p* !hen acids are added to the !ater" Acid additions #enerally come rom rain or sno!+ thou#h soil sources are also also import important ant in some some areas" areas" Alkali Alkalinity nity increa increases ses as !ater  !ater  dissol$es dissol$es rocks containin# containin# calcium carbonate such as calcite ca lcite and limestone" Alkalinity is sometimes incorrectly used interchan#eably !ith basicity !ith basicity"" 7or e-ample+ the p* o a solution can be lo!ered by the addition o 23/" This !ill reduce the basicity ho!e$er+ the alkalinity !ill remain unchan#ed.9hen your body is hi#hly acidic your body !ill leach alkaline minerals to balance your p*" This means it dra!s calcium rom your teeth and bones+  potass  potassium ium rom rom your muscles muscles and ner$es ner$es++ ma#nesiu ma#nesium m rom your arteri arteries+ es+ and sodium sodium rom your  your   joints  joints"" no nort rtuna unatel tely y it’ it’ss not lookin lookin# # to to rele release ase any o the acid acid to-i to-ins ns that that your your body is stori storin# n# in it’s it’s at cells" So in the end+ our bodies hold onto the acidic to-ins and !e loose $aluable bone supporti$e minerals" 9e all ha$e a delicate p* and our bodies preer a sli#htly alkaline en$ironment" 9hen the oods !e consume push our p* to!ard acidity our bodies ind alkaline minerals stored internally to cure the imbalance" 9hile our bodies are ama&in# machines and ha$e the ability to do this and keep us in healthy p* ran#e+ the process o repairin# this imbalance re%uires a se$ere loss o the $ery minerals you !ork hard to supplement daily" ;$en more scary+ acidity is a silent killer+ causin# inlammation in the body !hich is the root o all disease" Alkalinity o natural !ater is determined by the soil and bedrock throu#h !hich it passes"

 The main sources or natural alkalinity are rocks !hich contain carbonate+ bicarbonate+ and hydro-ide compounds"
2on$ersely+ areas rich in #ranites and some con#lomerates and sandstones may ha$e lo! alkalinity and thereore poor po or buerin# capacity"

WHO Guideline Value: Value:

9orld 9orld health or#ani&ation su##ested a #uideline $alue or alkalinity: 

6o! alkalinity = 50m#lit as 2a234



Medium alkalinity 50  /50 m#lit as 2a234



Alkalinity > /50 m#lit as 2a234

PH ini!ators: A pH ini!ator  is a halochromic chemi chemical cal compoun compound d added in small amounts to a solution so the p* the p* (acidity acidity or  or basicity  basicity)) o the solution can be determined $isually" *ence+ a p* indicator is a chemical chemical detector  detector or hydronium or hydronium ions  ions (*43?) or hydro#en ions (* ?) in the Arrh Arrhenius enius model model""  @ormally+ the indicator causes the color  color o o the the solu soluti tion on to chan# chan#ee depe dependi ndin# n# on the the p*" p*" ndicators ndicators can also sho! chan#e in other physical properties properties or e-ample+ e-ample+ olactory olactory indicators indicators sho! chan#e in their odor " The p* $alue o a neutral solution is "0" Solutions !ith a p* $alue  belo! "0 are considered acidic and solutions !ith p* $alue abo$e "0 are basic (alkaline)" Methyl oran#e: 4"5  1"5 .henolphthalein: 8"/ B C0"0 As most ost nat natural urally ly occu occurrrin# rin# or# or#anic anic comp compou ound ndss are are !eak !eak prot protol oly ytes tes+ carbo-ylic acids and acids  and amines amines++ p* indicators ind many applications in biolo#y and analytical chemistry" Moreo$er+ p* indicators orm one o the three main types o indicator compounds used in chemical analysis" 7or the %uantitati$e analysis o metal cations+ the use o comple-ometric indicators is preer preerred red+!h +!here ereas as the third third compoun compound d class+ class+ the redo- indic indicators ators++ are used in titrations in$ol$in# a redo- reaction as the basis o the analysis"

Apparatus: •

Stand +dropper+ beaker+ sucker"

•


Chemi!als: •

Methyl oran#e solution + tap !ater+ distilled !ater 

•

Standard solution ( */S31) ha$in# normality 0"0/

.rocedure: C" Take Take 50 ml o !ater !ater sample sample that is tap tap !ater in in a lask and note note the initial initial .* o the the !ater  sample" sample" Add si- drops o methyl oran#e indicator indicator in the sample (!ater)+ (!ater)+ note the initial initial readin# o the burette containin# */S31 (@D0"0/) /" Start the the titration titration till the the color chan#es chan#es and note the readin# readin# o the burette+ burette+ 2alculat 2alculatee the methyl oran#e alkalinity usin# the ormula alkalinity alkalinity D (inal readin#  initial initial readin#) E C0050 4" @o! add sisi- drops o methyl methyl oran#e oran#e in in the the second second !ater sample sample that is distilled distilled !ater  note the initial .* o the !ater sample " @ote the initial readin# o the burette and start the titration till the color chan#es to #ray and note the inal readin#" 1" Start the the titration titration till the the color chan#es chan#es and note the readin# readin# o the burette+ burette+ 2alculat 2alculatee the methyl oran#e alkalinity usin# the ormula alkalinity alkalinity D (inal readin#  initial initial readin#) E C0050 5" 2alculate 2alculate total alkalinity alkalinity by usin# usin# the ormula+ ormula+ Total Total alkalinity D (inal readin#  initial readin#) - C0050

"bservations an Cal!ulations: 1# $or $or tap tap wat water er: nitial p* o the tap !ater D F"4

Amount o !ater used D 50ml Golume Golume o the acid used D 1ml 7inal p* o tap !ater D 7ormula :  @C H GC D  @/ H G/ @C

@C

D

0"0/ H /050

D

0"008H 50H C000m#6

@C D

100m#6

%# $or $or ist istil ille le  water water:: Golume o !ater D 50ml Golume Golume o acid D /0ml nitial p* o !ater D 8"4 7inal p* o !ater D 7ormula:  @C H GC D @/ H G/  @C D 0"0/ H 150 @C D 0"00CFH 50 H C000 @C D 80m#6