Remarks:
When both acid and base are 1 Normal in concentration, indicators with effective ranges between pH 3 and 10.5 can be used. Suitable indicators include Methyl Orange, Bromocresol Green, Methyl Red, Methyl Purple, Bromothymol Blue, Phenol Red, Phenolphthalein and Thymolphthalein. When both the acid and base are 0.1 Normal, the ideal pH range is reduced to 4.5 to 9.5. Thus, Methyl Orange and Thymolphthalein are not as suitable as the others. With 0.01 Normal solutions, the ideal pH range is further limited to 5.5 - 8.5. See the indicator list and pH chart in the back of this catalog for details on suitable ranges for various indicators.
A basimetric standard such as Tris(hydroxymethyl)aminomethane can also be used to standardize Sulfuric Acid solutions. Methyl Red is a suitable indicator.
