Structure via PubChem · Public domain (PubChem)
Chemical data
- Formula
- C14H14N3NaO3S
- Molecular weight
- 327.34 g/mol
- IUPAC name
- sodium 4-[[4-(dimethylamino)phenyl]diazenyl]benzenesulfonate
- SMILES
- CN(C)C1=CC=C(C=C1)N=NC2=CC=C(C=C2)S(=O)(=O)[O-].[Na+]
- InChIKey
- STZCRXQWRGQSJD-UHFFFAOYSA-M
- Polar surface area
- 93.5 Ų
- H-bond donors
- 0
- H-bond acceptors
- 6
- Formal charge
- 0
via PubChem
Research
4,374 papersvia PubMed
Wikidata facts
- Mass
- 327.065357
- Image
- Methyl-orange-sample.jpg
Show 6 more facts
- Commons category
- Methyl orange
- canonical SMILES
- CN(C)C1=CC=C(C=C1)N=NC2=CC=C(C=C2)S(=O)(=O)[O-].[Na+]
- chemical formula
- C₁₄H₁₄N₃NaO₃S
- density
- 1.28
- melting point
- 300
- sRGB color hex triplet
- E32600
via Wikidata · CC0
~3 min read
Article
Methyl orange is a pH indicator frequently used in titration because of its clear and distinct color variance at different pH values. Methyl orange shows red color in acidic medium and yellow color in basic medium. Because it changes color at the pKa of a mid strength acid, it is usually used in titration of strong acids in weak bases that reach the equivalence point at a pH of 3.1-4.4. Unlike a universal indicator, methyl orange does not have a full spectrum of color change, but it has a sharp end point. In a solution becoming less acidic, methyl orange changes from red to orange and, finally, to yellow—with the reverse process occurring in a solution of increasing acidity.
Indicator colors