Volumetric analysis involves using a standard solution in a reaction with a well-defined end point to determine the concentration of another substance - Scottish Highers Chemistry - Question 4 - 2023

To accurately determine the concentration of a substance through volumetric analysis, the following procedures and equipment are used:

1. Preparation of Solutions

Firstly, a standard solution of known concentration is prepared. This involves accurately weighing a suitable primary standard, such as sodium chloride, and dissolving it in distilled water to achieve a precise molarity (e.g., 0.1 M).

2. Equipment Required

The following apparatus is essential:

• Burette: For delivering the titrant solution accurately.
• Pipette: To measure and transfer a specific volume of the analyte solution.
• Conical Flask: To hold the solution being titrated.
• Indicator: A chemical that changes color at the end point, such as phenolphthalein, which indicates neutrality in acid-base titrations.

3. Set Up of the Experiment

The experiment is set up by securing the burette above the conical flask. The known solution (titrant) is filled in the burette and is allowed to flow slowly into the measured volume of analyte in the conical flask.

4. Conducting the Titration

As the titrant is added, the mixture is constantly swirled. The addition continues until the indicator changes color, signaling that the endpoint has been reached.

5. Calculation

The volume of titrant used is recorded, and the concentration of the solution can then be calculated using the formula: $C_1V_1 = C_2V_2$ where:

• $C_1$ and $V_1$ are the concentration and volume of the titrant,
• $C_2$ and $V_2$ are the concentration and volume of the analyte.

6. Repetition and Accuracy

To ensure accuracy, the titration should be repeated several times until consistent results are achieved. This will help in minimizing errors and improving the reliability of the results.