Citric acid monohydrate
SIAL/33114 - puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., buffer substance, 99.5-102%
Synonym: 2-
CAS Number: 5949-29-1
Empirical Formula (Hill Notation): C6H8O7 · H2O
Molecular Weight: 210.14
EC Number: 201-069-1
MDL Number: MFCD00149972
Linear Formula: HOC(COOH)(CH2COOH)2 · H2O
Product Type: Chemical
| agency | reag. ISO |
| reag. Ph. Eur. | |
| USP/NF | |
| anion traces | chloride (Cl-): ≤5 mg/kg |
| oxalate (C2O42-): ≤50 ppm | |
| phosphate (PO43-): ≤10 mg/kg | |
| sulfate (SO42-): ≤20 ppm | |
| assay | 99.5-100.5% (calc. on anhydrous substance) |
| 99.5-102% | |
| cation traces | Ca: ≤50 mg/kg |
| Cu: ≤5 mg/kg | |
| Fe: ≤3 ppm | |
| Pb: ≤2 ppm | |
| Zn: ≤5 mg/kg | |
| form | solid |
| grade | ACS reagent |
| puriss. p.a. | |
| ign. residue | ≤0.01% (as SO4) |
| impurities | ≤0.005% insolubles in water |
| ≤2 ppm heavy metals (as Pb) | |
| 7.5-9.0% water (Karl Fischer) | |
| InChI | 1S/C6H8O7.H2O/c7-3(8)1-6( |
| InChI key | YASYEJJMZJALEJ-UHFFFAOYSA |
| pKa | (1) 3.13, (2) 4.76, (3) 6.4 |
| Quality Level | 200  |
| SMILES string | OC(CC(O)(C(O)=O)CC(O)=O)= |
| suitability | complies for appearance of solution |
| complies for reaction against H2SO4 |
| Application: | Citric acid monohydrate may be used in the preparation of tris-citrate buffer and Otto I isolation buffer used in bioprotocols. It may also be used to improve the release of diltiazem hydrochloride from melt extruded matrix tablets. |
| General description: | Citric acid monohydrate is an organic acid. Its molar enthalpy of solution in water has been reported to be ΔsolHm (298.15K, m = 0.0203molkg-1) = (29061 ± 123)Jmol-1. |
| Symbol |  GHS07 |
| Signal word | Warning |
| Hazard statements | H319 |
| Precautionary statements | P305 + P351 + P338 |
| Hazard Codes | Xi |
| Risk Statements | 36 |
| Safety Statements | 26 |
| RIDADR | NONH for all modes of transport |
| WGK Germany | WGK 1 |
| Flash Point(F) | 345.0 °F |
| Flash Point(C) | 173.9 °C |
| Purity | 99.5-100.5% (calc. on anhydrous substance); 99.5-102% |
| UNSPSC | 12352100 |