33325

Potassium phthalate monobasic

puriss. p.a., buffer substance, ≥99.5%

• Synonym(s): KHP, Phthalic acid monopotassium salt, Potassium biphthalate, Potassium hydrogen phthalate
• Linear Formula: HOOCC₆H₄COOK
• CAS Number: 877-24-7
• Molecular Weight: 204.22
• Beilstein/REAXYS Number: 3637128
• EC Number: 212-889-4
• MDL number: MFCD00013070
• UNSPSC Code: 12352100
• PubChem Substance ID: 57648795
• NACRES: NA.21

Properties

• grade: puriss. p.a.
• assay: ≥99.5%
• form: solid
• loss: ≤0.2% loss on drying, 105 °C
• pH: 4
• mp: 295-300 °C (dec.) (lit.)
• anion traces: chloride (Cl^-): ≤10 mg/kg; sulfate (SO₄^2-): ≤50 mg/kg
• cation traces: Cd: ≤5 mg/kg; Co: ≤5 mg/kg; Cu: ≤5 mg/kg; Fe: ≤5 mg/kg; Na: ≤100 mg/kg; Ni: ≤5 mg/kg; Pb: ≤5 mg/kg; Zn: ≤5 mg/kg
• SMILES string: [K+].OC(=O)c1ccccc1C([O-])=O
• InChI: 1S/C8H6O4.K/c9-7(10)5-3-1-2-4-6(5)8(11)12;/h1-4H,(H,9,10)(H,11,12);/q;+1/p-1
• InChI key: IWZKICVEHNUQTL-UHFFFAOYSA-M

Description

General description

Potassium phthalate monobasic is the monopotassium salt of phthalic acid. It has been proposed as a certified reference material (CRM) under ISO/IEC 17025 and ISO Guide 34 accreditation. Its spectral shift, multiplicity, solubility and relaxation times in different solvents have been reported.[1]

Application

Potassium phthalate monobasic may be used as a buffer to maintain pH = 2.39 and 4.52, during the dispersive ionic liquid-liquid microextraction coupled with liquid chromatography and UV detection of drug (benznidazole and nifurtimox) levels in human plasma.[2] It has been used as internal standard certified reference material (CRM) for the high performance (HP)-quantitative NMR spectroscopic (qNMR) determination of various organic compounds.[1]

Safety Information

• Storage Class: 13 - Non Combustible Solids
• wgk_germany: WGK 3
• flash_point_f: 387.1 °F - Pensky-Martens closed cup
• flash_point_c: 197.3 °C - Pensky-Martens closed cup
• ppe: Eyeshields, Gloves, type N95 (US)