European Pharmacopoeia 2.2.5

) is defined as the ratio of the mass of a certain volume of a substance at temperature to the mass of an equal volume of water at temperature

For substances with melting points near 20 °C, the chapter allows measurements at other temperatures (e.g., 25 °C or 15 °C) but with a clear statement and conversion using correction factors—though this is discouraged for official tests. european pharmacopoeia 2.2.5

| Problem | Possible Cause | Solution | |---------|----------------|----------| | Non-reproducible weights | Air bubbles in pycnometer | Degas sample (ultrasonic bath) | | Drifting results | Temperature fluctuation | Check bath thermostat; insulate | | Pycnometer weight changes | Dirty or wet exterior | Use lint-free cloth; calibrate cleanliness SOP | | Digital meter error | Viscosity mismatch | Use appropriate viscosity correction factor | | Outliers with solids | Air trapped in solid pores | Vacuum degas before weighing | ) is defined as the ratio of the

) in pharmaceutical testing. In the pharmaceutical industry, density is more than just a physical property; it is a critical quality control parameter used to identify substances, ensure the correct concentration of active ingredients, and monitor the stability of liquid formulations. 1. Definition and Core Concepts Eur. 2.2.5 with similar chapters:

The ratio of the mass of a given volume of the substance to the mass of an equal volume of water at a specified temperature.

It is useful to compare Ph. Eur. 2.2.5 with similar chapters: