A standard solution plays a very important role in volumetric analysis because it has a known and accurate concentration. It is used to determine the concentration of an unknown solution.
Roles of a Standard Solution:
- Reference for measurement:
- It serves as a benchmark to compare against the unknown solution.
- Accurate calculation of unknown concentration:
- By measuring the volume of the standard solution needed to react completely with the analyte, the concentration of the unknown can be calculated using stoichiometry.
- Ensures precision and reliability:
- Using a standard solution reduces errors and improves the accuracy of titration results.
- Types of standard solutions:
- Primary standard: Very pure, stable, and can be weighed accurately (e.g., sodium carbonate, potassium hydrogen phthalate).
- Secondary standard: Standardized against a primary standard when a primary standard is not available (e.g., hydrochloric acid, sodium hydroxide).
In short:
A standard solution is a solution of known concentration used as a reference in titrations to determine the concentration of unknown solutions accurately.