Benzoate sodium estimation
Sodium Benzoate:
Molecular Formula: C7H5NaO2
Mol. Wt. 144.1
C7H5NaO2, calculated on a dried basis, comprises not less than 99.0 percent nor more than 100.5 percent of Sodium Benzoate.
Description - Powder, flakes, or granules that are white, crystalline, or granular, odorless or weakly fragrant, and hygroscopic.
Methods for preparing 0.1N solutions of HClO4 and standardizing them:
Add about 30 ml of acetic anhydride to 900 ml glacial acetic acid and stir well after adding 8.5 ml of 72% HClO4 while stirring and keep the mixture for 24 hours. Anhydrous acetic acid, which is completely absorbed by HClO4 and glacial acetic acid, leaves the solution almost anhydrous. Before adding acetic anhydride to HClO4, it must be diluted with glacial acetic acid, since it will explode when HClO4 and acetic anhydride are combined.
Standardization of HCIO4:
HClO4 is standardized by adding 25 ml of glacial acetic acid to 500 mg of potassium acid phthalate then adding few drops of 5% water/volume crystal violet into glacial acetic acid as an indicator. 0.1 HClO4 is titrated with this solution. After titration, the solution changes color from blue to green.
Assay procedure:
Anhydrous glacial acetic acid, heated to 50 degrees if necessary and cooled with a saline solution of approximately 0.25 g of Sodium Benzoate. Test the solution with perchloric acid 0.1 M and 1-naphtholbenzein solution as an indicator. Measure the solution in a blank.
Equivalent or IP factor:
0.01441 g of C7H5NaO2 would be equivalent to one ml of 0.1 M perchloric acid.
Where,
The amount consumed at the endpoint is determined by X ml
Perchloric acid normality after standardization = Normality calculated
0.1 N (theoretically) is the normality given
Sodium Benzoate:
Molecular Formula: C7H5NaO2
Mol. Wt. 144.1
C7H5NaO2, calculated on a dried basis, comprises not less than 99.0 percent nor more than 100.5 percent of Sodium Benzoate.
Description - Powder, flakes, or granules that are white, crystalline, or granular, odorless or weakly fragrant, and hygroscopic.
Methods for preparing 0.1N solutions of HClO4 and standardizing them:
Add about 30 ml of acetic anhydride to 900 ml glacial acetic acid and stir well after adding 8.5 ml of 72% HClO4 while stirring and keep the mixture for 24 hours. Anhydrous acetic acid, which is completely absorbed by HClO4 and glacial acetic acid, leaves the solution almost anhydrous. Before adding acetic anhydride to HClO4, it must be diluted with glacial acetic acid, since it will explode when HClO4 and acetic anhydride are combined.
Standardization of HCIO4:
HClO4 is standardized by adding 25 ml of glacial acetic acid to 500 mg of potassium acid phthalate then adding few drops of 5% water/volume crystal violet into glacial acetic acid as an indicator. 0.1 HClO4 is titrated with this solution. After titration, the solution changes color from blue to green.
Assay procedure:
Anhydrous glacial acetic acid, heated to 50 degrees if necessary and cooled with a saline solution of approximately 0.25 g of Sodium Benzoate. Test the solution with perchloric acid 0.1 M and 1-naphtholbenzein solution as an indicator. Measure the solution in a blank.
Equivalent or IP factor:
0.01441 g of C7H5NaO2 would be equivalent to one ml of 0.1 M perchloric acid.
Where,
The amount consumed at the endpoint is determined by X ml
Perchloric acid normality after standardization = Normality calculated
0.1 N (theoretically) is the normality given
Estimation of ephedrine hydrochloride
Ephedrine Hydrochloride:
Formula: C10H15NO, HCl
Mol. Wt. 201.7
The dried content of Ephedrine Hydrochloride should not be less than 99.0 percent, nor more than 101.0 percent.
Ephedrine Hydrochloride:
Formula: C10H15NO, HCl
Mol. Wt. 201.7
The dried content of Ephedrine Hydrochloride should not be less than 99.0 percent, nor more than 101.0 percent.
Description - A white powder with no odor; colorless crystals. It is photosensitive.
Ephedrine Hydrochloride can be estimated as follows:
Methods for preparing 0.1N solutions of HClO4 and standardizing them:
Add about 30 ml of acetic anhydride to 900 ml glacial acetic acid and stir well after adding 8.5 ml of 72% HClO4 while stirring and keep the mixture for 24 hours. Anhydrous acetic acid, which is completely absorbed by HClO4 and glacial acetic acid, leaves the solution almost anhydrous. The reaction between HClO4 and acetic anhydride will be explosive if HClO4 is not diluted with glacial acetic acid first.
Standardization of HCIO4:
It is recommended to use 25 ml of glacial acetic acid along with 500 mg of potassium acid phthalate and few drops of 5% crystal violet crystal in glacial acetic acid to standardize HClO4. 0.1 HClO4 is added to this solution to titrate the solution. After titration, the solution changes color from blue to green.
Assay procedure
The solution should consist of 0.17 g of Ephedrine Hydrochloride dissolved in 10 ml of mercuric acetate dissolved in 50 ml of acetone melted in 10 ml of mercuric acetate. To determine the color, titrate 0.1 M perchloric acid with a saturated solution of methyl orange in acetone, using 1 ml of the solution as an indicator. Titrate a blank solution.
Perchloric acid in 0.1 M solution equals 0.02017 g of C10H15NO, HCl per ml
Where,
X ml = Titrant consumption at end
Perchloric acid normality after standardization = Normality calculated
0.1 N (theoretically) is the normality given
Ephedrine Hydrochloride can be estimated as follows:
Methods for preparing 0.1N solutions of HClO4 and standardizing them:
Add about 30 ml of acetic anhydride to 900 ml glacial acetic acid and stir well after adding 8.5 ml of 72% HClO4 while stirring and keep the mixture for 24 hours. Anhydrous acetic acid, which is completely absorbed by HClO4 and glacial acetic acid, leaves the solution almost anhydrous. The reaction between HClO4 and acetic anhydride will be explosive if HClO4 is not diluted with glacial acetic acid first.
Standardization of HCIO4:
It is recommended to use 25 ml of glacial acetic acid along with 500 mg of potassium acid phthalate and few drops of 5% crystal violet crystal in glacial acetic acid to standardize HClO4. 0.1 HClO4 is added to this solution to titrate the solution. After titration, the solution changes color from blue to green.
Assay procedure
The solution should consist of 0.17 g of Ephedrine Hydrochloride dissolved in 10 ml of mercuric acetate dissolved in 50 ml of acetone melted in 10 ml of mercuric acetate. To determine the color, titrate 0.1 M perchloric acid with a saturated solution of methyl orange in acetone, using 1 ml of the solution as an indicator. Titrate a blank solution.
Perchloric acid in 0.1 M solution equals 0.02017 g of C10H15NO, HCl per ml
Where,
X ml = Titrant consumption at end
Perchloric acid normality after standardization = Normality calculated
0.1 N (theoretically) is the normality given
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