Chemical Solutions
Indicators
JSA provides a complete line of chemical indicators used when titrating metal finishing process solutions.
- Most common indicators are in stock and ready to ship (Example – Phenolphthalein, Methyl Orange, Bromocresol Purple, etc.)
- Indicators are certified traceable to NIST and all come with expiration dates and certificates of analysis
- Multiple concentrations of each indicator available
- Container sizes range from 120 mL to 20 Liter
- Need a non-standard indicator? Custom formulations available upon request
Description
An indicator is a chemical substance used in titrations to signal the endpoint of a reaction between an acid and a base (or between other reactants).
Indicators are typically weak acids or bases that change color at a specific pH range. When a titrant is added to a solution containing the analyte, the pH of the solution changes as the reaction proceeds. The indicator will change color when the pH reaches a certain point, which corresponds to the completion of the reaction, and thereby the concentration of the component or product in solution.
For example, phenolphthalein is a common indicator used in alkaline cleaner titrations. It is pink in alkaline solutions and turns colorless as the pH becomes more acidic, indicating the endpoint of the titration.
Another example is methyl orange, which changes from red to yellow in the pH range of about 3.1 to 4.4, making it suitable for titrations involving strong acids and weak bases.
Choosing the appropriate indicator depends on the specific titration being performed, particularly the pH at which the endpoint occurs.
