Preparation and Standardization of 1 N HCl Solution

Preparation and Standardization of 1 N HCl Solution procedure wash the burette with the D. W. and the titrant (HCl) fill the bttburettewith HCl toalll...

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Preparation and Standardization of 1 N HCl Solution Glass ware and instruments: ‰ preparation

beaker

washing bottle

glass stirrer

volumetric flask

graduated cylinders

fume hood

Preparation and Standardization of 1 N HCl Solution Glass ware and instruments: ‰ standardization

conical flask

tripod stand

burette

wire gauze

burette stand

Bunsen burner

burette clamp

Preparation and Standardization of 1 N HCl Solution Glass ware and instruments: ‰ standardization

spatula

watch glass

electrical balance

oven

Preparation and Standardization of 1 N HCl Solution ‰p preparation p of 100 mL of 1 N HCl solution Dilute 9 mL of HCl with distilled water to a final volume l off 100 mL L using i a 100 mLL volumetric l ti flask.

N1 :the normality of concentrated HCl used V1 :the volume of concentrated HCl to be used for dilution N2 :the requested normality of HCl (1 N in our experiment) V2 :final volume after dilution (100 mL in our experiment)

Preparation and Standardization of 1 N HCl Solution

N :the normality of the concentrated acid % : the th weight i ht by b weight i ht concentration t ti off the th acid id sp. gr. : the specific gravity of the acid eq. w eq wt. :thee equ equivalent v e we weight g oof thee acid cd

Preparation and Standardization of 1 N HCl Solution ‰ standardization Na2CO3 + 2HCl

2NaCl + H2O + CO2

¾ anhydrous sodium carbonate is used as the primary standard ¾ methyl red is used as the indicator

yyellow

faint p pink

Preparation and Standardization of 1 N HCl Solution ‰ titration apparutus pp

Preparation and Standardization of 1 N HCl Solution ‰ burette adjusment j

Preparation and Standardization of 1 N HCl Solution ‰ burette adjusment j

Preparation and Standardization of 1 N HCl Solution ‰ procedure p ƒ wash the burette with the D. W. and the titrant (HCl) ƒ fill the th burette b tt with ith HCl to t a level l l (adjust ( dj t it) ƒ dissolve the primary standard (Na2CO3) in enough D. W. ((100 mL)) usingg the conical flask ƒ add 2 drops of methyl red ƒ start titration by adding HCl drop wise with continuous stirring ti i until til the th solution l ti becomes b f i t pink faint i k ƒ heat the solution to boiling so that the colour changes back into yyellow,, cool,, and titrate again g until the faint p pink colour is no longer affected by boiling ƒ record the volume of HCl used and calculate the normality lit

Preparation and Standardization of 1 N HCl Solution ‰ procedure p

end d point i t (faint pink)

Preparation and Standardization of 1 N HCl Solution ‰ calculations HCl

Na2CO3

N :the th normality lit off HCl to t be b calculated l l t d V : the volume of HCl used (in mL) wt. : thee we w weight g oof sod sodium u ccarbonate bo e ((in g) eq. wt. : the equivalent weight of sodium carbonate