Process of Standardizing Solution of Silver Nitrate Using Hydrochloric Acid

Homestandard preparation 0.1 N Silver Nitrate Solution Preparation & Standardization

0.1 N Silver Nitrate Solution Preparation & Standardization

0.1 N Silver Nitrate Solution

 Preparation of 0.1 N Silver Nitrate Solution

• Dry 17.5 g of silver nitrate (AgNO3) at 105°C for 1 h. Cool in a desiccator.
• Transfer 16.99 g of the dried AgNO3 to a 1-L volumetric flask.
• Add 500 ml of water, swirl to dissolve the AgNO3, dilute to the mark with water, and mix. Store the solution in a tightly stoppered amber-glass bottle.

NOTE —If desired the solution may also be prepared on a determinate basis by weighing the dried silver nitrate accurately and diluting the solution carefully to volume.

 Standardization of 0.1 N Silver Nitrate Solution

Warning—Nitrobenzene, used in this section, is extremely hazardous when absorbed through the skin or when its vapor is inhaled. Such exposure may cause cyanosis; pro-
longed exposure may cause anemia. Do not get in eyes, on skin, or on clothing. Avoid breathing vapor. Use only with adequate ventilation.

• Dry 0.3 g of sodium chloride (NaCl) at 105°C for 2 h. Cool in a desiccator.
• Weigh accurately 0.28 ± 0.01 g of the dried NaCl and transfer to a 250-mL glass-stoppered conical flask.
• Add 25 mL of water, swirl to dissolve the NaCl, and
• Add 2 mL of nitric acid (HNO3). Add from a volumetric pipet, 50 mL of the AgNO3 solution, while mixing thoroughly,
• Add 1 mL of ferric ammonium sulfate solution (FeNH 4(SO4)2·12H2O, 80 g/L) and 5 mL of nitrobenzene (Warning, see).
• Stopper the flask and shake vigorously to coagulate the precipitate. Rinse the stopper into the flask with a few milliliters of water and titrate the excess of AgNO3 with ammonium thiocyanate solution (NH4SCN) until the first permanent reddish-brown color appears and persists after vigorous shaking for 1 min.
• Preparation of ammonium thiocyanate. Solution does not need to be standardized for use here. (See Note )
• Designate the volume of NH4SCN solution required for the titration as Volume I.
• Using the same volumetric pipet used in , transfer 50 mL of the AgNO3 solution to a clean, dry, 250-mL, glass-stoppered conical flask.
• Add 25 mL of water, 2 mL of HNO3, 1 mL of FeNH4(SO4)2·12H2O solution, stopper the flask, and shake vigorously.
• Rinse the stopper into the flask with a few milliliters of water and titrate the AgNO3 solution with NH4SCN solution until the first permanent reddish-brown color appears and persists after vigorous shaking for 1 min.
• Designate the volume of NH4SCN solution consumed as Volume II.
• Measure accurately, from either a burette or a volumetric pipet, 2.0 mL of the AgNO3 solution, designate the exact volume as Volume III, and
• Transfer to a 100-mL, glass stoppered conical flask.
• Add 25 mL of water, 2 mL of HNO3, 1 mL of FeNH4(SO 4)2·12H2O solution, and 5 mL of nitrobenzene, (Warning, see ) stopper the flask, and shake vigorously.
• Rinse the stopper into the flask with a few milliliters of water and titrate the AgNO3 solution with NH4SCN solution until the first permanent reddish-brown color appears and persists after vigorous shaking for 1 min. Designate the volume of NH4SCN solution consumed as Volume IV.

NOTE —The ammonium thiocyanate titrant used in the three titrations must be from the same, well-mixed solution. The nitrobenzene used in each titration must also be from the same, well-mixed container.

 Calculation

Calculate the normality of the AgNO3 solution as follows:

  A = B / 0.05844  * (C - D)

where:

A = normality of the AgNO3 solution,

B = grams of NaCl used,

C = volume of AgNO 3 solution consumed by the total chloride = 50 − [Volume I * (50/Volume II)], and

D = volume of AgNO3 solution consumed by any chloride ion in the nitrobenzene = Volume III − [Volume IV * (50/Volume II)].

 Stability

Re-Standardize monthly.

Process of Standardizing Solution of Silver Nitrate Using Hydrochloric Acid

Source: https://www.chemwifi.com/2020/09/01-n-silver-nitrate-solution.html

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