calomel electrode

The calomel electrode is used to work out the electrode potential of half cells.

The calomel electrode is a reference electrode, especially in older publications.

Saturated calomel electrode and glass electrode are often used in conjunction to determine the pH of water.

The reference electrode may be a silver chloride electrode or a calomel electrode.

The following data are presented relative to the saturated calomel electrode (SCE) in acetonitrile:

The calomel electrode contains mercury, which poses much greater health hazards than the silver metal used in the Ag/AgCl electrode.

Liquid mercury is a part of popular secondary reference electrode (called the calomel electrode) in electrochemistry as an alternative to the standard hydrogen electrode.

Typical half-wave reduction potentials for 1,2 compounds are versus the standard calomel electrode (SCE) while those for the 1,3-isomers are 0.2V.

Unlike the majority of organic compounds, ferrocene undergoes a one-electron oxidation at a low potential, around 0.5 V vs. a saturated calomel electrode (SCE).

The Saturated calomel electrode (SCE) is a reference electrode based on the reaction between elemental mercury and mercury(I) chloride.

When saturated the redox potential of the calomel electrode is +0.2444 V vs. SHE at 25 C, but slightly higher when the chloride solution is less than saturated.

For instance, lead ion is reduced at a potential of -0.60 V (relative to the saturated calomel electrode), while zinc ions are not; this allows the determination of lead in the presence of zinc.

The transmural potential difference was measured between a NaCl filled subcutaneous cannula on one forearm and the luminal contents by means of calomel electrodes, using agar bridges between the cannula and the perfusion tube.

The more complex references such as standard hydrogen electrode, saturated calomel electrode, or silver chloride electrode(specific concentration) can not directly mix the analyte solution for fear the electrode will fall apart or interact/react with the analyte.

Thus, 3-methylthiophene polymerizes in acetonitrile and tetrabutylammonium tetrafluoroborate at a potential of about 1.5 V vs. SCE (saturated calomel electrode), while unsubstituted thiophene polymerizes at about 1.7 V vs. SCE.