Reagents and Indicators R-13-
1
Analytical Methods of the Member Companies of the
Corn Refiners Association, Inc.
Accepted 4-15-86
MERCURIC NITRATE SOLUTION
PREPARATION
0.02
N Mercuric Nitrate Solution: For chloride determination. Dissolve 3.3 g of
reagent grade mercuric nitrate (Hg(NO
3)2) in about 100 mL of purified water
containing 0.25 mL of concentrated nitric acid (70% HNO
3, sp g 1.42). Dilute to
1 L with purified water, and mix.
STANDARDIZATION
Dry a quantity of analytical grade sodium chloride (NaCl) 30 minutes at 105
°C;
cool in desiccator. Dissolve 0.8241 g of dry sodium chloride in purified water,
dilute to 1 L volume, and mix.
Pipet 5.00 mL of the above sodium chloride solution, containing 2.5 mg chloride,
into each of three 250 mL glass stoppered Erlenmeyer flasks. Add 85 mL of
purified water, 10 mL of diphenylcarbazone indicator solution, 1 mL of 30%
hydrogen peroxide solution, and 1.0 mL of 0.5
N nitric acid solution (Note 1) to
each of the flasks. Stopper flasks and swirl contents. Prepare a reagent blank in a
250 mL Erlenmeyer flask containing 90 mL of purified water, 10 mL of
diphenylcarbazone indicator solution, 1 mL of 30% hydrogen peroxide solution,
and 1.0 mL of 0.5
N nitric acid solution; mix. Titrate the blank with mercuric
nitrate solution to the purple indicator end point. Color development near the end
point is slow, and as much as 30 seconds should be allowed between titrant drops
to facilitate full indicator color development (Note 2). Titrate the three standards
in the same manner to the same color end point. Observe and record the titers.
Calculate average normality.
CALCULATION
(mL Hg(NO ) Titer - Blank)×35.45
2.5mg
Normality =
3 2
Reagents and Indicators R-13-
2
MERCURIC NITRATE SOLUTION
⎯ continued
NOTES AND PRECAUTIONS
1. Treatment with hydrogen peroxide destroys interfering sulfites by oxidation
to sulfates, and the nitric acid addition adjusts acidity to the proper level
(pH about 2.5).
2. Care should be exercised as the end point is approached, and it is expedient
to observe the reaction mixture over a white surface. End point detection is
facilitated by running the blank first, and then titrating the standards to
match the color of the blank.
We can find chlorides content as sodium chloride from 500 ppm with out any difficulty. p v rao
I want to assmue the the readers of this answer have know the details theory and calculations about Mohr method if not u can refer to Any analytical text for reference. Well, Bromide and Chloride can not be determine simultaneously in a sample using Mohr method , the reason be that the indicator use for each of them is different. and there will be problem in the procedure if ones try to determine both simultaneously. To determine Chloride Ion, Ammonium or Potassium Thiocynate is used as indicator and the sample must be neutral or slightly acidic. while Eosin indicator is use for the determination of Bromide Ion and the same neutral solution is prefer for this purpose, the solution must be adjusted to neutral either by adding small amount of Nitric acid or by adding small amount of carbonate as the case maybe. But, in the determination of each of them Silver Nitrate is use for the titration of both and this is the similarity they shared and the experimental procedure is quite the same. Olajire Mojeed
1- done only in neutral medium. 2- all the cations which give insolublld be chromate must be absent or removed before titration. 3-titration of Ag+ with Cl- is not feasible. 4- not suitable for I- and SCN-
(mass /volume)x100
no you cant. your thinking of the shake n bake one pot method and one has to use amonia nitrate, not urea.
- Potentiometric titration with silver nitrate (AgNO3) - Titration (manual) with silver nitrate (AgNO3) or mercuric thiocyanate - Chronopotentiometry - Using ISE (Ion Selective Electrode) for Cl-
We can find chlorides content as sodium chloride from 500 ppm with out any difficulty. p v rao
This method uses a back titration with potassium thiocyanate to determine the concentration of chloride ions in a solution.Before the titration an excess volume of a standardized silver nitrate solution is added to the solution containing chloride ions, forming a precipitate of silver chloride (AgCl). The term 'excess' is used as the moles of silver nitrate added are known to exceed the moles of sodium chloride present in the sample so that all the chloride ions present will react.Ag+ + Cl- AgCl(s) (Ksp = 1.70 × 10−10)Excess WhiteExcess of Ag+ is back titrated with SCN-.
Examples: silver chloride, silver fluoride, silver iodide, silver bromide, silver astatide, silver sulfide, silver nitrate etc. For silver halogenides a method of preparation is the reaction between silver nitrate and a salt containing the halogen.
its a method for determination of reducing sugars
I want to assmue the the readers of this answer have know the details theory and calculations about Mohr method if not u can refer to Any analytical text for reference. Well, Bromide and Chloride can not be determine simultaneously in a sample using Mohr method , the reason be that the indicator use for each of them is different. and there will be problem in the procedure if ones try to determine both simultaneously. To determine Chloride Ion, Ammonium or Potassium Thiocynate is used as indicator and the sample must be neutral or slightly acidic. while Eosin indicator is use for the determination of Bromide Ion and the same neutral solution is prefer for this purpose, the solution must be adjusted to neutral either by adding small amount of Nitric acid or by adding small amount of carbonate as the case maybe. But, in the determination of each of them Silver Nitrate is use for the titration of both and this is the similarity they shared and the experimental procedure is quite the same. Olajire Mojeed
bcz titration is da worst method
Egg
The electrometric method of pH determination provides a single value dependent on the concentration of hydrogen ions in the aqueous solution being tested. The colorimetric method of pH determination uses acid-base indicators to provide a range of values for a solution's pH, and is therefore less accurate than the electrometric method.
if u have sodium chloride solution just heat it..water will get evaporated leaving only sodium chloride
chromatography?
K+ and Cl- react to form KCl (potassium chloride)