33114

Citric acid monohydrate

ACS reagent grade, 99.5-102%, solid, puriss. p.a., reag. ISO, reag. Ph. Eur., buffer substance

• Synonym(s): 2-hydroxy-1,2,3-propanetricarboxylic acid monohydrate
• Linear Formula: HOC(COOH)(CH₂COOH)₂ · H₂O
• CAS Number: 5949-29-1
• Molecular Weight: 210.14
• NACRES: NA.21
• PubChem Substance ID: 57648756
• UNSPSC Code: 12352100
• EC Number: 201-069-1
• MDL number: MFCD00149972
• Beilstein/REAXYS Number: 4018641
• Assay: 99.5-100.5% (calc. on anhydrous substance), 99.5-102%
• Form: solid

Properties

• Product Name: Citric acid monohydrate, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., buffer substance, 99.5-102%
• InChI key: YASYEJJMZJALEJ-UHFFFAOYSA-N
• InChI: 1S/C6H8O7.H2O/c7-3(8)1-6(13,5(11)12)2-4(9)10;/h13H,1-2H2,(H,7,8)(H,9,10)(H,11,12);1H2
• SMILES string: OC(CC(O)(C(O)=O)CC(O)=O)=O.O
• grade: ACS reagent, puriss. p.a.
• agency: USP/NF, reag. ISO, reag. Ph. Eur.
• assay: 99.5-100.5% (calc. on anhydrous substance), 99.5-102%
• form: solid
• impurities: ≤0.005% insolubles in water, ≤2 ppm heavy metals (as Pb), 7.5-9.0% water (Karl Fischer)
• ign. residue: ≤0.01% (as SO₄)
• pKa: (1) 3.13, (2) 4.76, (3) 6.4
• anion traces: chloride (Cl^-): ≤5 mg/kg, oxalate (C₂O₄^2-): ≤100 ppm, phosphate (PO₄^3-): ≤10 mg/kg, sulfate (SO₄^2-): ≤20 ppm
• cation traces: Ca: ≤50 mg/kg, Cu: ≤5 mg/kg, Fe: ≤3 ppm, Pb: ≤2 ppm, Zn: ≤5 mg/kg
• suitability: complies for appearance of solution, complies for reaction against H₂SO₄
• functional group: carboxylic acid
• Quality Level: 200

Description

General description

Citric acid monohydrate is an organic acid. Its molar enthalpy of solution in water has been reported to be Δ_solH_m (298.15K, m = 0.0203molkg^-1) = (29061 ± 123)Jmol^-1.[1]

Application

Citric acid monohydrate may be used in the preparation of tris-citrate buffer[2] and Otto I isolation buffer used in bioprotocols.[3] It may also be used to improve the release of diltiazem hydrochloride from melt extruded matrix tablets.[4]

Safety Information

• pictograms: GHS07
• signalword: Warning
• hcodes: H319,H335
• pcodes: P261 - P264 - P271 - P280 - P304 + P340 + P312 - P305 + P351 + P338
• Hazard Classifications: Eye Irrit. 2 - STOT SE 3
• target_organs: Respiratory system
• Storage Class: 11 - Combustible Solids
• wgk: WGK 1
• flash_point_f: 345.0 °F - closed cup
• flash_point_c: 173.9 °C - closed cup
• ppe: dust mask type N95 (US), Eyeshields, Gloves