Mathematics Revision OF ELECTROCHEMISTRY

### ELECTROCHEMICAL CELL

=> color{green}("Electrochemistry") : It is the study of production of electricity from energy released during spontaneous chemical reactions and the use of electrical energy to bring about non-spontaneous chemical transformations.
=> color{green}("Galvanic cell") : A galvanic cell is an electrochemical cell that converts the chemical energy of a spontaneous redox reaction into electrical energy.

### ELECTROCHEMICAL SERIES

=> color{green}("Electrochemical series") : The standard reduction potentials of a large number of electrodes have been measured by using the SHE. The arrangement of elements in order of increasing or decreasing order of standard reduction potential values is called the electrochemical series or activity series.

### CONDUCTANCE

=> color{green}("Resistance") : The property of substance which resists the flow of electricity through it is called resistance.
=> color{green}("Conductivity") : The inverse of resistivity, called conductivity (specific conductance) is represented by the symbol, κ (Greek, kappa).
=> color{green}("Electrical Conductance") : Electrical conductance through metals is called metallic or electronic conductance and is due to the movement ofelectrons.
=> color{green}("Ionic Conductivity") : The conductance of electricity by ions present in the solutions is called electrolytic or ionic conductance.
=> color{green}("Molar Conductivity") : Λ_m can be defined as the conductance of the electrolytic solution kept between the electrodes of a conductivity cell at unit distance but having area of cross section large enough to accommodate sufficient volume of solution that contains one mole of the electrolyte.

### KOHLRAUSCH LAW

=>color{green}("Limiting Molar Conductivity") :The molar conductivity at infinite dilution or approximately zero concentration.
=> color{green}("Kohlrausch law") : The limiting molar conductivity of an electrolyte is the sum of molar conductivities of the cations and anions each multiplied by the number of ions present in one formula unit of electrolyte.

### ELECTROLYSIS

=> color{green}text(Electrolytic Cell) : In an electrolytic cell external source of voltage is used to bring about a chemical reaction. The electrochemical processes are of great importance in the laboratory and the chemical industry.
=> color{green}text(First Law) : The amount of chemical reaction which occurs at any electrode during electrolysis by a current is proportional to the quantity of electricity passed through the electrolyte (solution or melt).
=> color{green}text(Second Law) : The amounts of different substances liberated by the same quantity of electricity passing through the electrolytic solution are proportional to their chemical equivalent weights.

### BATTERY

=> color{green}text(Battery) :Arrangement of electrochemical cells connected in series used as a source of energy to get a desired voltage.
=> color{green}text(Primary cell) : In the primary batteries, the reaction occurs only once and after use over a period of time, battery becomes dead and cannot be reused again.
=> color{green}text(Secondary cell) : A secondary cell after use can be recharged by passing current through it in the opposite direction so that it can be used again.

### FUEL CELL

=> color{green}text(Fuel cells) : Galvanic cells that are designed to convert the energy of combustion of fuels like hydrogen, methane, methanol, etc. directly into electrical energy are called fuel cells.

### CORROSION

=> color{green}text(Corrosion) : The process of slowly eating away of metal due to attack of atmospheric gases on the surface of metals resulting in the formation of undesirable compounds is termed as corrosion.