Methyl yellow

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Methyl yellow
Methyl yellow.svg
Names
Preferred IUPAC name
N,N-Dimethyl-4-(phenyldiazenyl)aniline
Other names
4-Dimethylaminoazobenzene
p-Dimethylaminoazobenzene
DAB
N,N-Dimethyl-4-phenylazoaniline
N,N-Dimethyl-4-aminoazobenzene
Butter Yellow
Solvent Yellow 2
C.I. 11020
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.000.414
EC Number 200-455-7
RTECS number BX7350000
UNII
Properties
C14H15N3
Molar mass 225.30 g·mol−1
Appearance Yellow crystals
Melting point 111–116 °C (232–241 °F; 384–389 K)
decomposes[1]
13.6 mg/l
log P 4.58
Hazards
Main hazards Carcinogen[2]
GHS pictograms The skull-and-crossbones pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)The health hazard pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)[1]
GHS signal word Danger
H301, H351[1]
P281, P301+310[1]
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
US health exposure limits (NIOSH):
PEL (Permissible)
OSHA-regulated carcinogen[2]
REL (Recommended)
Ca[2]
IDLH (Immediate danger)
Ca [N.D.][2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Methyl yellow, or C.I. 11020, is a chemical compound which may be used as a pH indicator.

Methyl yellow (pH indicator)
below pH 2.9 above pH 4.0
2.9 4.0

In aqueous solution at low pH, methyl yellow appears red. Between pH 2.9 and 4.0, methyl yellow undergoes a transition, to become yellow above pH 4.0.

Safety[edit]

It is a possible carcinogen.[2] As "butter yellow", the agent had been used as a food additive before its toxicity was recognized.[3] The result from consuming such chemicals is tumors on the liver.

See also[edit]

Structurally similar compounds:

References[edit]

External links[edit]