Millipore Sigma Vibrant Logo
 
Lab Technical Resources
 

pH Indicator Solution Preparation

IndicatorTransition IntervalColor ChangeIndicator Solution (preparation)
Malachite green oxalate
(C.I. No. 42000)		 0.0 Yellow 2.0 Green-blue 0.1g in 100ml water
Brilliant-green
(C.I. No. 42040)		 0.0 Yellow 2.6 Green 0.1g in 100ml water
Eosin yellowish
(C.I. No. 45380)		 0.0 Yellow 3.0 Green fluorescence 0.1g in 100ml water
Erythrosine B
(C.I. No. 45430)		 0.0 Orange 3.6 Red 0.1 in 100ml water
Methyl green
(C.I. No. 42590)		 0.1 Yellow 2.3 Blue 0.1g in 100ml water
Methyl violet
(C.I. No. 42535)		 0.1 Yellow 2.7 Violet 0.1g in 100ml ethanol (20%)
Picric acid
(C.I. No. 10305)		 0.2 Colorless 1.0 Yellow 0.1g in 100ml ethanol (70%)
Cresol red 0.2 Red 1.8 Yellow 0.1g in 100ml ethanol (20%)
Crystal violet
(C.I. No. 42555)		 0.8 Yellow 2.6 Blue-violet 0.1g in 100ml ethanol (70%)
m-Cresol purple 1.2 Red 2.8 Yellow 0.004g in 100ml ethanol (20%)
Thymol blue 1.2 Red 2.8 Yellow 0.04g in 100ml ethanol (20%)
p-Xylenol blue 1.2 Red 2.8 Yellow 0.1g in 100ml ethanol (50%)
2,2',2",4,4'-
Pentamethoxytriphenylcarbinol		 1.2 Red 3.2 Colourless 0.1g in 100ml ethanol (96%)
Eosin bluish
(C.I. No. 45400)		 1.4 Colorless 2.4 Fluorescent pink 0.1g in 100ml water
Quinaldine red 1.4 Colorless 3.2 Pink 0.1g in 100ml ethanol (60%)
2,4-Dinitrophenol 2.8 Colorless 4.7 Yellow 0.1g in 100ml ethanol (70%)
Methyl yellow
(C.I. No. 11020)		 2.9 Red 4.0 Yellow-orange 0.1-0.5g in 100ml ethanol (90%)
Bromochlorophenol 3.0 Yellow 4.6 Blue-violet 0.1g in 100ml ethanol (20%) to 100ml w/water
Bromophenol blue 3.0 Yellow 4.6 Blue-violet 0.1g in 100ml ethanol (20%)
Congo red
(C.I. No. 22120)		 3.0 Blue 5.2 Yellow-orange 0.2g in 100ml water
Methyl orange
(C.I. No. 13025)		 3.1 Red 4.4 Yellow-orange 0.04g in 100ml ethanol (20%)
Methyl orange solution      
Mixed indicator 4.5 acc. to Mortimer 4.3 Red 5.2 Blue 250ml
Bromocresol green 3.8 Yellow 5.4 Blue 0.1g in 100ml ethanol (20%)
2.5-Dinitrophenol 4.0 Colorless 5.8 Yellow 0.05-0.1g in 100ml ethanol (70%)
Methyl red
(C.I. No. 13020)		 4.4 Red 6.2 Yellow-orange 0.1g in 100ml ethanol (96%)
Methyl red sodium salt
(C.I. No. 13020)		 4.4 Red 6.2 Yellow-orange 0.1g in 100ml ethanol (96%)
Mixed indicator 5 4.4 Red-violet 5.8 Green 250ml
Chlorophenol red 4.8 Yellow 6.4 Purple 0.1g in 100ml ethanol (20%)
Litmus
(C.I. No. 1242)		 5.0 Red 8.0 Blue 4g in 100ml water
Bromocresol purple 5.2 Yellow 6.8 Purple 0.1g in 100ml ethanol (20%)
Bromophenol red 5.2 Orange-yellow 6.8 Purple 0.1g in 100ml ethanol
4-Nitrophenol 5.4 Colourless 7.5 Yellow 0.2g in 100ml ethanol (96%)
Bromoxylenol blue 5.7 Yellow 7.5 Blue 0.1g in 100ml ethanol (96%)
Bromothymol blue 6.0 Yellow 7.6 Blue 0.1g in 100ml ethanol (20%)
Phenol red 6.4 Yellow 8.2 Red-violet 0.1g in 100ml ethanol (20%)
3-Nitrophenol 6.6 Colourless 8.6 Yellow-orange 0.3g in 100ml ethanol (96%)
Neutral red
(C.I. No. 50040)		 6.8 Blue-red 8.0 Orange-yellow 0.3g in 100ml ethanol (70%)
Cresol red 7.0 Orange 8.8 Purple 0.1g in 100ml ethanol
1-Naphtolphthalein 7.1 Brownish 8.3 Blue-green 0.1g in 100ml ethanol (50%)
m-Cresol purple 7.4 Yellow 9.0 Purple 0.04g in 100ml ethanol (20%)
Thymol blue 8.0 Yellow 9.6 Blue 0.04g in 100ml ethanol (20%)
p-Xylenol blue 8.0 Yellow 9.6 Blue 0.1g in 100ml ethanol (50%)
Phenolphthalein 8.2 Colorless 9.8 Red-violet 0.1g in 100ml ethanol (96%)
Phenolphthalein solution
(1% in ethanol)		 8.0 Colorless 10.0 Red-violet 1.0g in 100ml ethanol (96%)
Phenolphthalein solution
(0.375% in methanol)		 8.0 Colorless 10.0 Red-violet 0.375g in 100ml methanol (99%)
Thymolphthalein 9.3 Colourless 10.5 Blue 0.1g in 100ml ethanol (50%)
Alkali blue
(C.I. No. 42750)		 9.4 Violet 14.0 Pink 0.1g in 100ml ethanol (96%)
Alizarin yellow GG
(C.I. No. 14025)		 10.0 Light-yellow 12.1 Brownish-yellow 0.1g in 100ml water
Titan yellow
(C.I. No. 19540)		 12.0 Yellow 13.0 Red 0.1g in 100ml ethanol (20%)
Indigo carmine
(C.I. No. 73015)		 11.5 Blue 13.0 Yellow 0.25g in 100ml ethanol (59%)
Epsilon blue 11.6 Orange 13.0 Violet 0.1g in 100ml water