Electrochemistry

Electrochemistry

Electrochemistry

 It is the branch of chemistry which deals with the study of interconversion of electric energy and chemical energy into one another

Electrolytic conduction

The flows of current due to movement of Ions through the solution of An electrolytic is called electrolytic conduction

Conductors

 the substance which allows the electric city to pass through them are called as conductors

Type of conductors

 there are of two types of conductors

Electronic conductors: in which the flow of electricity is due to the flow of electrons example metal graphite etc
Electrolyte: the substance which dissociates into ions and their solution pass electricity example solution of HCL H2SO4 NACL NaOH etc.
Non-electrolyte the substance which does not dissociate into ions and their solution does not pass electricity example sugar will cause urea ethyl alcohol etc

Type of electrolyte
 there is of two types electrolyte

Strong electrolyte: that are those electrolytes which almost dissociate into ions completely in aqueous solution.
Example: HCL, KOH, H2SO4, NaCl, NaOH, etc.
Weak electrolytes: desert electrolytes that dissociate into ions only up to a small extent in aqueous solution.
Example: CH3COOH, HCN, Ca(OH)2, NH4OH, etc.

Difference between metallic conductors and electrolyte conductors

Resistance (R):

it is the ratio of potential difference to the current flowing through across the conductors.

Conductance:

it is the reciprocal of electric resistance

The specific resistance of resistivity

it is observed that resistance of a conductor is directly proportional to its length and inversely proportional to its area of cross-section

Where p is a constant called as specific resistance or resistivity it's l is equal to 1 centimeter and a is equal to 1 CM²
Then R=p
Specific resistance or resistivity may be defined as the resistance of a conductor whose length is 1 cm and the time area cross-section is 1 centimeter ²

Specific conductance of specific conductivity 

the reciprocal of specific resistance and resistivity is known as specific conductance of specific conductivity or conductivity

the specific conductivity of a solution is defined as the conductance of a solution of 1 cm length and having one-centimeter² area of cross-section

Equivalent conductivity

It is the conductivity power of all ions produced by dissolving 1 gram equivalent of electrolyte in the solution
Or
equivalent conductivity of a solution at dilution v is defined as the conductance of all the ions produced from one gram.

The equivalent of the electrolyte dissolved in v cm³ of the solution when the distance between the electrode is 1 cm and the area of the electron is so large that whole of the solution contains between them it is represented by lambda


where is the concentration of the solution in gram equivalent per liter ( or normality ).

Molar conductivity

it is the conducting power of all ions produced by dissolving 1 mole of an electrolyte in the solution
Or
molar conductivity of a solution and illusion v is defined as the conductance of all the highest produced from one mall of the electrolyte dissolved in v cm³ of the solution when the distance between the electrode is 1 centimeter and the area of the electrode is so large that wool of the solution is contained between them.

Where she is the concentration of the solution in mole per liter.

Experimental measurement of conductance and specific

Electrolyte conductance

conductance is the reciprocal of resistance conductance can be finding out by measurement of resistance and for the resistance weak used principle of Wheatstone bridge method.
It consists of four arms containing the resistance R1, R2, R3, R4. R1 is the value of variable resistance and R2 is unknown resistance.

When a null point is obtained that is there is no deflection in the galvanometer G. Then
R1/R2 = R3/R4

Knowing the value of R1,  R3, R4, R2 can be calculated.

Cell constant

where l is the distance between the electrode and a is the area of cross-section of each electrode for a particle cell l/a is constant and his constant is called cell constant it is usually represent buy G. Then-


the cell constant is generally not calculated from the value of l and a because that are difficult to measure for a given cell it is it can be determined by measuring the conductance of the solution whose specific conductivity is known

Cell constant= specific conductance/ observed conductance