Indicator paper is an instrument of chemical analysis. It is made by taking white filter paper and impregnating it with a solution of an acid-base indicator, in this case a solution of congo red. Dried and cut into test strips, the paper is packaged and goes on sale.
It is sufficient to dip one end of the strip into the solution to be tested and evaluate the change (or lack of change) in the color of the strip. If the congo red indicator strip turns blue, then the solution is acidic.
This method of determining acidity is cheap, fast, economical and safe, so it is very popular in various laboratories.
Scope of application
– Determination of media acidity.
– Calculation of the neutralization point of the interaction of acid and alkali.
– Diagnosis of the formation of lactic acid in the medium with B. Coli bacteria.