A5348912
Methyl red , ACS , 493-52-7
Synonym(s):
2-(4-Dimethylaminophenylazo)benzoic acid;4-Dimethylaminoazobenzene-2′-carboxylic acid;Acid Red 2;Methyl red (C.I. 13020);Methyl red indicator solution
CAS NO.：493-52-7
Empirical Formula: C15H15N3O2
Molecular Weight: 269.3
MDL number: MFCD00002425
EINECS: 207-776-1
| Pack Size | Price | Stock | Quantity |
| 25G | RMB63.20 | In Stock |
|
| 50g | RMB111.20 | In Stock |
|
| 100g | RMB175.20 | In Stock |
|
| 500g | RMB719.20 | In Stock |
|
| others | Enquire |
Update time: 2022-07-08
PRODUCT Properties
| Melting point: | 179-182 °C (lit.) |
| Boiling point: | 412.44°C (rough estimate) |
| Density | 0.839 g/mL at 25 °C |
| vapor density | 9.3 (vs air) |
| refractive index | 1.5930 (estimate) |
| Flash point: | 11 °C |
| storage temp. | Store at +5°C to +30°C. |
| solubility | ethanol: soluble1mg/mL |
| Colour Index | 13020 |
| form | Solid |
| pka | 4.95(at 25℃) |
| color | Reddish-violet |
| Odor | Odorless |
| PH Range | 4.4(red)-6.3(yellow) |
| Water Solubility | Practically insoluble in water. Soluble in alcohol, acetic acidSoluble in ethanol. Insoluble in water. |
| λmax | 410nm, 530nm, 427nm, 519nm |
| Merck | 14,6119 |
| BRN | 750102 |
| Stability: | Stable. Incompatible with strong oxidizing agents. |
| Major Application | Waveguides, LED sensors, photoresists, liquid crystals, sol-gel matrix, optical sensors, paints, toys, detection of thiols, food freshness sensors, dental product, saliva sampling method, detecting lactic acid, carbohydrates |
| InChIKey | CEQFOVLGLXCDCX-MSUUIHNZSA-N |
| CAS DataBase Reference | 493-52-7 |
| IARC | 3 (Vol. 8, Sup 7) 1987 |
| NIST Chemistry Reference | Benzoic acid, 2-[[4-(dimethylamino)phenyl]azo]-(493-52-7) |
| EPA Substance Registry System | Methyl red (493-52-7) |
Description and Uses
As indicator in 0.1% alcoholic solution; pH: 4.4 red, 6.2 yellow. Used for titrating NH3, weak organic bases, e.g., alkaloids; not suitable for organic acids, except oxalic and picric acid. Methyl red is easily reduced, thereby losing its color, and readings should be made promptly. It is gradually being replaced by sulfonphthalein indicators, such as bromcresol green, which are more stable and exhibit a sharper change in color.
Safety
| Symbol(GHS) |    GHS02,GHS07,GHS08 |
| Signal word | Danger |
| Hazard statements | H225-H319-H371 |
| Precautionary statements | P210-P260-P280-P308+P311-P337+P313-P403+P235 |
| Hazard Codes | Xn,T,F,Xi,C,N |
| Risk Statements | 10-20/21/22-68/20/21/22-68-36/38-23/25-11-36/37/38-34-51/53-39/23/24/25-23/24/25 |
| Safety Statements | 36/37-24/25-22-45-33-24-16-7-36-26-36/37/39-61 |
| RIDADR | UN 1170 3/PG 2 |
| WGK Germany | 1 |
| RTECS | DG8960000 |
| TSCA | Yes |
| HazardClass | 3 |
| PackingGroup | II |
| HS Code | 29270000 |
| Hazardous Substances Data | 493-52-7(Hazardous Substances Data) |
