How to measure a Redox Potential

What is a Redox Potential?

Oxidation Reduction Potential (ORP or REDOX Potential) measures an aqueous system’s capacity to either release or accept electrons from chemical reactions. When a system tends to accept electrons it is an oxidizing system. When it tends to release electrons, it is a reducing system.

When are Redox measurements required?

There are a number of different reasons why someone would want to measure the redox potential of a solution. Continuous or frequent monitoring using REDOX electrodes can be extremely useful for early detection of issues related to a change from the steady or “stable state” of an aqueous system. These reactions can be brought about by contamination or undesired chemical or environmental interference. Another common use of REDOX measurement is in disinfection measurement where the effectiveness of decontamination can be monitored and any residue of bleaching agents detected.

How does it work?

The REDOX combination electrode consists of a platinum sensor and an Ag/AgCl reference half-cell built in a standard 12mm electrode body. The measurements are displayed in millivolts (mV). Most REDOX measurements are made in dynamic environments where a reaction is taking place. This is indicated by the increase or decrease in the circulations of free electrons. Typical applications include corrosion monitoring or rusting for example. As the ratio of Fe(3+) to Fe(2+) increases the potential of the surrounding solution changes to reflect this.

The TRUEscience system allows you to attach a Redox electrode to the SMARTcap, and wirelessly connect to an android tablet or phone. This allows you to use the computing power of android to access enriched features such as storing readings into jobs whilst giving each reading a name with notes, GPS and images. Other features allow you to log your results, and carry out a quality control check, all in an intuitive app format.

For more information about measuring redox or if you would like to take a closer look at the TRUEscience system please get in touch on 01954 233 120 or email us on support@camlab.co.uk.