How to Prepare and Standardize 0.05 M Silver Nitrate (SOP)

1.0 Scope:

This guide covers how to prepare and standardize a 0.05 M silver nitrate solution.

2.0 Apparatus

• 1000 ml and 250 ml volumetric flasks
• 250 ml conical flask with a glass stopper
• 10 ml and 50 ml volumetric pipettes
• 100 ml graduated burette

3.0 Reagents

• Silver nitrate (AR grade)
• Sodium chloride (AR grade)
• Acetic acid (AR grade)
• Eosin solution
• Methanol (AR grade)

Preparing the eosin solution:

Mix 0.5 g of eosin with enough purified water to make 100 ml. Store it in an amber glass bottle with a stopper.

4.0 Preparation of 0.05 M Silver Nitrate Solution

Mix 8.5 g of silver nitrate into enough purified water to make a total volume of 1000 ml.

5.0 Standardization of 0.05 M Silver Nitrate Solution

• Weigh out exactly 0.05 g of sodium chloride. Make sure you dried it at 110°C for 2 hours first.
• Dissolve it in 5 ml of purified water.
• Add 5 ml of acetic acid, 50 ml of methanol, and 0.15 ml of eosin solution.
• Stir the mixture, ideally using a magnetic stirrer.
• Titrate it with the 0.05 M silver nitrate solution.

Note: 1 ml of 0.05 M silver nitrate equals 0.002922 g of NaCl.

6.0 Calculation

Use this formula to find the molarity:

Where:
M = Molarity of the silver nitrate
W = Weight of the sodium chloride in grams
V = Volume of the silver nitrate used in ml

7.0 Storage

Keep the solution in an amber glass bottle with a stopper.

8.0 Reference

Based on IP 1996, page 212.