Grade 12Physical Chemistry

What is the effect of external EMF in the function of Daniel cell??

Purvipallavi Dash

6 Years agoGrade 12

3 Answers

Arun

6 Years ago

If the cell is not set up reversibly, (for instance most common galvanic cells (aka 'batteries') are set up for no charging) there is no chemical reaction to make use of the voltage difference, and the amps will increase until the voltage resistance drop into and through the electrolyte in the cell matches the external applied voltage

Vikas TU

6 Years ago

Dear student

if Ew>E, then that also means that
RT/nFln[([Ox]w / [Red]w)] > [RT/nF] ln([Ox]/[Red])
Finally, you get that this situation implies an increase of Ox at the expense of Red, which is what you would expect from an electrolytic cell - the supply of electrical energy causes electrochemical reactions.

If you apply a potential that is below E, the only difference would be that Ox would decrease and Red would increase, but the overall treatment remains the same.

MANTHAN RAO

6 Years ago

When no current is being drawn from a reversible cell, the potential difference across its terminals, or open circuit voltage (OCV), is known as the ELECTROMOTIVE FORCE or EMF of the cell.If the cell is not set up reversibly (For instance most common galvanic cells( A galvanic cell or voltaic cell, named after Luigi Galvani or Alessandro Volta, respectively, is an electrochemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell.) are set up for no charging) there is no chemical reaction to make use of the voltage difference, and the amps will increase until the voltage resistance drop into and through the electrolyte in the cell matches the external applied voltage