Electrochemical equivalent

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In chemistry, the electrochemical equivalent (Eq or Z) of a chemical element is the mass of that element (in grams) transported by a specific quantity of electricity, usually expressed in grams per coulomb of electric charge. [1] The electrochemical equivalent of an element is measured with a voltameter.

Contents

Definition

The electrochemical equivalent of a substance is the mass of the substance deposited to one of the electrodes when a current of 1 ampere is passed for 1 second, i.e. a quantity of electricity of one coulomb is passed.

The formula for finding electrochemical equivalent is as follows:

where is the mass of substance and is the charge passed. Since , where is the current applied and is time, we also have

Eq values of some elements in kg/C

ElementElectrochemical equivalent
Silver (Ag)1.118×10^(-6)

0.000118gm/c

Copper (Cu)3.295×10^(-7)
Gold (Au)6.812×10^(-7)
Iron (Fe)2.894×10^(-7)
Zinc (Zn)3.389×10^(-7)
Hydrogen (H2)1.044×10^(-7)
Sodium (Na)2.387×10^(-7)
Potassium (K)4.055×10^(-7)
Oxygen (O2)8.28×10^(-8)
Aluminum (Al)9.36×10^(-8)

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References

  1. "Definition of ELECTROCHEMICAL EQUIVALENT". www.merriam-webster.com. Retrieved 2023-10-14.