Salt bridge is a U-shaped tube containing a semi-solid paste of some inert electrolyte like KCl, KNO₃, NH₄Cl, etc. in agar-agar and gelatin. An inert electrolyte is one which:

(a) Does not react chemically with the solutions in either of the component.

(b) Does not interface with the net cell reaction.

Function of the salt bridge

In the electrochemical cell a salt bridge serves two very important functions:

(i) It allows the flow of current by completing the circuit 

(ii) It maintains electrical neutrality.

The transference of electrons from anode to cathode leads to net positive charge around the anode due to increase in the concentration of cations and net negative charge around the cathode due to excess of anions in solutions. The positive charge around the anode will prevent electrons to flow out from it and the negative charge around the cathode will prevent the inflow of electrons at it. The reaction would then, stop, and no current will flow. The salt bridge comes to aid and restores the electrneutrality of the solutions in the two compartments. It contains concentrated solutions of an inert electrolyte the ions of which are not involved in electrochemical reactions. The anions of the electrolyte in the salt bridge migrate to the anode compartment and cations to the cathode compartment. Therefore, the salt bridge prevents the buildup of charges and preserves the flow of current. In the electrochemical cell, the salt bridge can be replaced by the porous partition which allows the migration of ions but does not allow mixing of the two solutions.

 

 

Posted Date: 6/26/2012 2:10:01 AM | Location : United States

Ask an Expert

Related Discussions:- Explain salt bridge with its functions., Assignment Help, Ask Question on Explain salt bridge with its functions., Get Answer, Expert's Help, Explain salt bridge with its functions. Discussions

Write discussion on Explain salt bridge with its functions.
Your posts are moderated

Write your message here..

Related Questions

Show the chemical properties of aluminium, Q. Show the chemical properties ... Q. Show the chemical properties of Aluminium? Aluminium has a very high affinity for oxygen; this is reflected in high exothermic heat of formation of Al 2 0 3 (-1676 kJ mol -

Claisen-schmidt reaction, Claisen-Schmidt Reaction: In this exercise, ... Claisen-Schmidt Reaction: In this exercise, you will make 2,2,6-trimethyl-5-phenylheptan-3-one by a reaction sequence which involves a Claisen-Schmidt  Reaction followed by th

Ammonical smell, how can we identify the ammonical smell and punjent smell?... how can we identify the ammonical smell and punjent smell?

Mention the product of onion and garlic, Onion and Garlic Onions (A. c... Onion and Garlic Onions (A. cepa), and garlic (A. sativam), have been used in traditional and folk medicine for over 4000 years.  Disorders for which both garlic and onions ha

Clch2ch2ch2coph +koh+meoh -> the product is...?, ClCH 2 CH 2 CH 2 COPh + Me... ClCH 2 CH 2 CH 2 COPh + Methanoic acid ---------------->   CH2-(CH2)-CH2-CO-C 6 H 6

Purification tecnics, how many methods to remove color impurities in chemic... how many methods to remove color impurities in chemical compounds?

#lanthaide actinide, why lanthanides and actinides are known as inner trans... why lanthanides and actinides are known as inner transition elements

Coordination chemistry, A compound exists in 2 forms. One them produces 2mo... A compound exists in 2 forms. One them produces 2moles of AgBr while the other produces 1mole of AgBr with AgNO3

Checal bonding, how can you balance k+o2 how can you balance k+o2

Help, what is the trend for ionization energy and metals in the periodic ta... what is the trend for ionization energy and metals in the periodic table