| Indicator |
pH Range |
Quantity of indicator per 10 mL |
Acid |
Alkali |
1.0 Universal
indicator
|
1-14
|
1 drop 0.1% soln. in water |
red
|
violet
|
1.1 Methyl
violet
|
0.2-3.0
|
1-2 drops 0.1% soln. in water |
yellow
|
violet
|
1.2 Thymol
blue (1st range)
|
1.2-2.8 |
1-2 drops 0.1% soln. in water |
red |
yellow |
1.3 Orange IV
(Tropeolin OO)
|
1.3-3.2 |
1 drop 1% soln. in water |
red |
yellow |
1.4 Benzopurpurin 4B
|
1.2-4.0
|
1 drop 1% soln. in water in 90% alc. |
violet
|
red
|
1.5 Methyl yellow
|
2.9-4.0
|
1 drop 0.1% soln. in water |
red
|
yellow
|
| 1.6 Methyl orange |
3.1-4.4 |
1 drop 0.1% soln. in water |
red |
orange
|
| 1.7 Bromophenol blue |
3.0-4.6 |
1 drop 0.1% soln. in water |
yellow |
purple |
| 1.8 Congo
red |
3.0-5.0
|
1 drop 0.1% soln. in water |
blue
|
red
|
| 1.9 Bromocresol green |
3.8-5.4 |
1 drop 0.1% soln. in water |
yellow |
blue |
| 2.0 Methyl red |
4.4-6.3 |
1 drop 0.1% soln. in water |
red |
yellow |
2.1 Chlorophenol red
|
5.4-6.8
|
1 drop 0.1% soln. in water |
yellow
|
red
|
2.2 Bromcresol purple
|
5.2-6.8
|
1 drop 0.1% soln. in water |
yellow
|
purple
|
2.3 Andrade's
acid fuchsin
|
5-8
|
1 drop 0.1% soln. in water |
pink
|
yellow
|
| 2.4 Litmus
|
4.5-8.3
|
1 drop 0.1% soln. in water |
red
|
blue
|
| 2.5 Bromothymol blue |
6.0-7.6 |
1 drop 0.1% soln. in water |
yellow |
blue |
| 2.6 Phenol
red |
6.4-8.4 |
1 drop 0.1% soln. in water |
yellow |
red |
| 2.7 Neutral red |
6.8-8.0 |
1 drop 0.1% soln. in 70% alc. |
red |
yellow |
2.8 Cresol red
|
7.2-8.8
|
1 drop 0.1% soln. in water |
yellow
|
red
|
2.9 Thymol
blue (2nd range)
|
8.0-9.6 |
1-5 drops 0.1% soln. in water |
yellow |
blue |
3.0 Phenolphthalein
|
8.2-10.0 |
1 5 drops 0.1% soln. in 90% alc. |
colourless |
red |
| 3.1 Thymolphthalein |
9.3-10.5 |
1 drop 0.1% soln. in 90% alc. |
colourless |
blue |
3.2 Alizarin yellow R
|
10.2-12.0 |
1-5 drops 0.1% soln. in 90% alc. |
yellow |
red |
3.3 Indigo carmine
|
11.6-13.0
|
1 drop 0.1% soln. in 50% ethanol soln. |
blue
|
yellow
|
3.4 Tropeolin 0
|
11.0-13.0 |
1 drop 0.1% soln. in water |
yellow |
brown-orange |
| 3.5 Nitramine |
11.0 13.0 |
1-2 drops 0.10% soln. in 70% alc. |
colourless |
brown-orange |
| 3.6 Trinitrobenzene |
12.0-13.4 |
1 drop 0.1% soln. in water |
colourless |
orange |