Chemical Purity Levels

Chemical Purity Levels

1. CP (Chemically Pure)

  • Suitable for general applications.

  • Mid-range purity level, good for most common laboratory uses.

  • May not meet strict ACS reagent grade standards.

2. USP/NF Grade

  • Meets standards set by the United States Pharmacopeia (USP) and the National Formulary (NF).

  • Used in pharmaceuticals and medical applications.

3. Analytical Reagent Grade (AR)

  • High purity chemicals for analytical laboratory use.

  • Commonly used in research and quality control.

4. HPLC Grade

  • Quality standard for solvents and chemicals in high-performance liquid chromatography.

  • Highly pure, special treatments to remove impurities.

5. Spectroscopic Grade

  • Highly pure materials for spectroscopy applications.

6. Primary Standard Grade

  • Chemical substance with purity > 99.98%.

  • Stable for accurate weighing to create known concentration solutions.

  • Common examples: sodium carbonate, potassium hydrogen phthalate, potassium dichromate.