# Potassium hydrogen phthalate, C8H5KO4

Potassium hydrogen phthalate (C8H5KO4) is a white crystalline salt commonly referred to as KHP. Due to its high purity and stability, KHP is frequently utilized as a primary standard for acid-base titrations. This means it has a well-known and stable stoichiometry, which is essential for accurate volumetric analyses. Another key characteristic of KHP is its low hygroscopicity, allowing it to be easily weighed accurately without the worry of moisture absorption skewing the results. In the optics domain, as with many salts, KHP can be utilized to produce specific refractive properties when dissolved in a solvent or integrated within composite materials. Besides its laboratory applications, potassium hydrogen phthalate serves as a buffer solution and can be used in the preparation of certain pharmaceuticals.

## Other names

- Hydrogen potassium phthalate
- Phthalic acid potassium salt
- Potassium biphthalate
- Potassium acid phthalate
- 1,2-Benzenedicarboxylic acid
- Monopotassium salt
- KHP
- KHPh

## External links

- Potassium hydrogen phthalate - Wikipedia