Silver Nitrate

This article is compiled based on the United States Pharmacopeia (USP) – 2025 Edition

Issued and maintained by the United States Pharmacopeial Convention (USP)

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AgNO₃ 169.87 

Nitric acid silver(1+) salt; 

Silver(1+) nitrate CAS RN®: 7761-88-8; UNII: 95IT3W8JZE. 

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1 DEFINITION 

Silver Nitrate, powdered and then dried in the dark over silica gel for 4 h, contains NLT 98.0%  and NMT 102.0% of silver nitrate (AgNO₃). 

2 IDENTIFICATION 

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A. Identification Tests—General 〈191〉, Chemical Identification Tests, Silver

Add the following: 

B. Characteristic emission lines for silver at 328 and 338 nm from the Sample solution correspond to those of the Standard solution, as obtained in the Assay.

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C.

Sample solution: 100 mg/mL of Silver Nitrate in water  

Analysis: Add 1 drop of diphenylamine TS to the Sample solution, and then carefully superimpose it upon sulfuric acid. Acceptance criteria: A deep blue color appears at the zone of contact. 

3 ASSAY 

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Procedure 

Use water with a resistivity of NLT 18 megohm-cm to prepare the solutions. 

Blank solution: 2% (w/v) nitric acid in water 

Standard solution: 15 mg/L of USP Silver Nitrate RS in Blank solution 

Sample: Powder an appropriate portion of Silver Nitrate, and dry in the dark over silica gel for 4 h. 

Sample solution: 15 mg/L of Silver Nitrate in Blank solution from the Sample 

Instrumental conditions 

(See Plasma Spectrochemistry 〈730〉.) 

Mode: ICP–OES 

Analytical wavelengths: Characteristic emission line for silver at 338 nm. For Identification A, detect additional silver emission line at 328 nm. 

System suitability 

Sample: Standard solution 

Suitability requirements 

Relative standard deviation: NMT 1.0% from ve replicate analyses 

Drift: NMT 2.0%. Compare emission intensities from the Standard solution before and after the analysis of the Sample solution. Analysis 

Samples: Blank solution, Standard solution, and Sample solution 

Calculate the percentage of silver nitrate (AgNO₃) in the portion of Silver Nitrate taken: 

Result = [(r_U − r_B )/(r_S − r_B )] × (C_S/C_U) × 100 

r_U = emission intensity of silver from the Sample solution 

r_B = emission intensity of silver from the Blank solution 

r_S = emission intensity of silver from the Standard solution 

C_S = concentration of USP Silver Nitrate RS in the Standard solution (mg/L)  

C_U = concentration of Silver Nitrate in the Sample solution (mg/L) 

Acceptance criteria: 98.0%–102.0%  

4 SPECIFIC TESTS 

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Clarity and Color of Solution 

Sample solution: 100 mg/mL of Silver Nitrate in water  

Acceptance criteria: The solution is clear and colorless. 

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Copper 

Sample solution: 100 mg/mL of Silver Nitrate in water  

Analysis: To 5 mL of the Sample solution add 6 N ammonium hydroxide, dropwise, until a precipitate rst formed is just dissolved. Acceptance criteria: No blue color is produced. 

5 ADDITIONAL REQUIREMENTS 

Packaging and Storage: Preserve in tight, light-resistant containers. 

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USP Reference Standards 〈11〉 

USP Silver Nitrate RS