Alessandro Volta

The electrochemical cells which generate an electric current are called voltaic cells or galvanic cells and those that generate chemical reactions, via electrolysis for example, are called electrolytic cells. A common example of a galvanic cell is a standard 1.5 volt cell meant for consumer use.

An electrolytic cell is made up of a positively charged anode and a negatively charged cathode. Electrolytic refining is a method mainly to purify metals such as copper, silver, zinc, tin, lead etc. The impure metal will be the anode and at the cathode metal ions get reduced and the pure metal gets deposited.

Since electrons flow from it, the anode in an electrolytic cell is positive, while the cathode is negative when electrons flow into it. In an electrolytic cell, an external voltage is applied to drive a nonspontaneous reaction. …

Solution: The electrolyte in the salt bridge is chosen so that it does not react with any of the chemicals used in the cell. The anion and cation have similar conductivity, and hence similar migratory speed. Potassium ion and Chlorine ion also have the same ionic mobilities.

One type of salt bridge consists of a U-shaped glass tube filled with a relatively inert electrolyte. It is usually a combination of potassium or ammonium ions and chloride or nitrate ions, which have similar mobility in solution.

KCl and KNO3 are used to maintain the neutrality of the cells. The salt bridge provides cations and anions to replace the ions lost or produced in the two half cells. Therefore, it do not disturb the neutrality of the cell but infact helps to maintain it. …

The main function of salt bridge is to maintain neutrality of the system . So , it provides negative ions to excess positive charge and positive ions to excess negative charge ,hence,keeping the system neutralised. For this reason KCL / KNO3 are used in a salt bridge .

Inert electrolytes like KCl , KNO3​ are used in salt bridge.

KCl and NH4Cl are not used in salt bridge in a cell containing Ag+,Hg2+andTl+ because they for insoluble metal chloride salts and metal salts get precipitated and cell will be destroyed.

Supporting electrolyte is also sometimes referred to as inert electrolyte or inactive electrolyte. Supporting electrolytes are widely used in electrochemical measurements when control of electrode potentials is required.

It is important to use an inert electrode in this situation because it will not react or participate in the reaction in the cell, just provide a surface area for the reaction to occur.

Iron is half filled in its valence shell so it is stable it do not want to react with other so it acts as inert electrode than other in the earth.

Active vs Inert Electrodes Active electrode is the electrode that actively takes part in the chemical reaction of the electrochemical cell. Inert electrode is an electrode that does not participate in the chemical reaction.

An active electrode is defined as a metal that is used in electrochemical cells. The active electrode is called ‘active’ because it actively participates in the chemical reaction. Also, it is used in electroplating. The most commonly used active electrode is the copper electrode.

Usually the inert electrodes such as platinum, gold and graphite used as a counter electrode. Because the nickel is dissolved, it is not recommended as the optimum counter electrode.

Inert means it is not reactive. An inert electrode is needed to conduct the electrons but it is not part of the redox reaction. You only need an inert electrode (like Pt or C(gr)) if your reactants cant function as an electrode (like I2 and Ce ions).