Acid-Base Indicators
Indicator | Handling range Colour change | Indicator solution (production) |
---|---|---|
Malachite green-Oxalate | 0,0 - 2,0 yellow - green blue | 0,1g in 100ml water |
Brillant green | 0,0 - 2,6 yellow - green | 0,1g in 100ml water |
Eosin (yellowish) | 0,0 - 3,0 yellow - green fluorescence | 0,1g in 100ml water |
Erythrosine B | 0,0 - 3,6 orange - reed | 0,1g in 100ml water |
Methyl green | 0,1 - 2,3 yellow - blue | 0,1g in 100ml water |
Methyl violet | 0,1 - 2,7 yellow - violet | 0,1g in 100ml Ethanol (20%) |
picric acid | 0,2 - 1,0 colourless - yellow | 0,1g in 100ml Ethanol (70%) |
Cresol red | 0,2 - 1,8 red - yellow | 0,1g in 100ml Ethanol (20%) or 0,04g in 1,05ml 0,1M NaOH and water up to 100ml |
Crystal violet | 0,8 - 2,6 yellow - blue violet | 0,1g in 100ml Ethanol (70%) |
Metacresol purple | 1,2 - 2,8 red - yellow | 0.04g in 100ml ethanol (20%) or 0.04g in 1.05ml 0.1M NaOH and make up to 100ml with water |
Thymol blue | 1,2 - 2,8 red - yellow | 0.04g in 100ml ethanol (20%) or 0.04g in 0.86ml 0.1M NaOH and make up to 100ml with water |
p- Xylenol blue | 1,2 - 2,8 red - yellow | 0.1g in 100ml ethanol (50%) or 0.04g in 0.98ml 0.1M NaOH and make up to 100ml with water |
2,2',2'',4,4'-Pentamethoxy red | 1,2 - 3,2 red - colourless | 0,1g in 100ml Ethanol (96%) |
Eosin, bluish | 1,4 - 2,4 colourless - pink fluorescent | 0,1g in 100ml Water |
Quinaldine red | 1,4 - 3,2 colourless - pink | 0,1g in 100ml Ethanol (60%) |
2,4-Dinitrophenole | 2,8 - 4,7 colourless - yellow | 0,1g in 100ml Ethanol (70%) |
Methyl yellow | 2,9 - 4,0 red - yellow orange | 0,1-0,5g in 100ml Ethanol (90%) |
Bromochlorophenol Blue | 3,0 - 4,6 yellow - blue violet | 0.1g in 100ml ethanol (20%) or 0.04g in 0.69ml 0.1M NaOH and make up to 100ml with water |
Bromophenol blue | 3,0 - 4,6 yellow - blue violet | 0.1g in 100ml ethanol (20%) or 0.04g in 0.6ml 0.1M NaOH and make up to 100ml with water |
Congo red | 3,0 - 5,2 blue - yellow orange | 0,2g in 100ml Water |
Methyl orange | 3,1 - 4,4 red - yellow orange | 0,04g in 100ml Water or 100ml Ethanol (20%) |
Mixed indicator 4.5 acc. to Mortimer | 4,3 - 5,2 red - blue | |
Bromocresol green | 3,8 - 5,4 yellow - blue | 0.1g in 100ml ethanol (20%) or 0.04g in 0.58ml 0.1M NaOH and make up to 100ml with water |
2,5-Dinitrophenole | 4,0 - 5,8 colourless - yellow | 0,05 - 0,1g in 100ml Ethanol (70%) |
Sodium alizarinesulfonate | 4,3 - 6,3 yellow - violet | 0,1g in 100ml Ethanol (50%) or 100ml Water |
Methyl red | 4,4 - 6,2 red - yellow orange | 0,1g in 100ml Ethanol (96%) |
Methyl red sodium salt | 4,4 - 6,2 red - yellow orange | |
mixed indicator 5 | 4,4 - 5,8 red-violet - green | |
Chlorophenol red | 4,8 - 6,4 yellow - violet | 0.1g in 100ml ethanol (20%) or 0.04g in 0.94ml 0.1M NaOH and make up to 100ml with water |
Litmus | 5,0 - 8,0 red - blue | 4g in 100ml Water |
Bromocresol purple | 5,2 - 6,8 yellow - purple | 0.1g in 100ml ethanol (20%) or 0.04g in 0.74ml 0.1M NaOH and make up to 100ml with water |
Bromophenol red | 5,2 - 6,8 orange-yellow - purple | 0.1g in 100ml ethanol (20%) or 0.04g in 0.94ml 0.1M NaOH and make up to 100ml with water |
4-Nitrophenol | 5,4 - 7,5 colorless - yellow | 0,2g in 100ml Ethanol (96%) or 0,08g in 100ml Water |
Bromoxylenol blue | 5,7 - 7,5 yellow -blue | 0,1g in 100ml Ethanol (96%) |
Alizarin | 5,8 - 7,2 yellow - red | 0,5g in 100ml Ethanol (96%) |
Bromothymol blue | 6,0 - 7,6 yellow - blue | 0.1g in 100ml ethanol (20%) or 0.04g in 0.64ml 0.1M NaOH and make up to 100ml with water |
Phenol red | 6,4 - 8,2 yellow - red violet | 0,1g in 100ml ethanol (20%) or 0,04g in 1,13ml 0,1M NaOH and make up to 100ml with water |
3-Nitrophenol | 6,6 - 8,6 colourless - yellow orange | 0,3g in 100ml Ethanol (96%) or 0,08g in 100ml Water |
Neutral red | 6,8 - 8,0 blue red - orange yellow | 0,3g in 100ml Ethanol (70%) |
Bromsulphthalein | 7,0 - 8,0 colorless - purple | 0,1g in 100ml Ethanol (96%) |
Cresol red | 7,0 - 8,8 orange - purple | 0,1g in 100ml ethanol (50%) or 0,04g in 1,05ml 0,1M NaOH and make up to 100ml with water |
Naphtholphthalein | 7,1 - 8,3 brownish - blue-green | 0,1g in 100ml Ethanol (96%) |
Metacresol purple | 7,4 - 9,0 yellow - purple | 0.04g in 100ml ethanol (20%) or 0.04g in 1.05ml 0.1M NaOH and make up to 100ml with water |
Thymol blue | 8,0 - 9,6 yellow - blue | 0.04g in 100ml ethanol (20%) or 0.04g in 0.86ml 0.1M NaOH and make up to 100ml with water |
p-Xylenol blue | 8,0 - 9,6 yellow - blue | 0.1g in 100ml ethanol (50%) or 0.04g in 0.98ml 0.1M NaOH and make up to 100ml with water |
Phenolphthalein | 8,2 - 9,8 colourless - red violet | 0,1g in 100ml Ethanol (96%) |
Thymolphthalein | 9,3 - 10,5 colourless - blue | 0,1g in 100ml Ethanol (50%) |
Alkali blue | 9,4 - 14,0 violet - pink | 0,1g in 100ml Ethanol (96%) |
Alizarin yellow GG | 10,0 - 12,1 light yellow - brownish yellow | 0,1g in 100ml Water |
Alizarin | 10,1 - 12,1 red - purple | 0,5g in 100ml Ethanol (96%) |
Titan yellow | 12,0 - 13,0 yellow - red | 0,1g in 100ml Ethanol (20%) |
Indigo carmine | 11,5 - 13,0 blue - yellow | 0,25g in 100ml Ethanol (50%) or 1g in 100ml Water |
Epsilon blue | 11,6 - 13,0 orange - violet | 0,1g in 100ml Water |
Source: Merck tables for the laboratory