Handout13-ElectroPotentiaJKl - CEM 834 ELECTROCHEMICAL...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
CEM 834 ELECTROCHEMICAL POTENTIAL FALL 2005 III. Junction Potential between Solutions The junction potential depends upon the mobilities of the ions, their concentrations, and their charges. For example, at the junction between solutions with two different concentrations of HCl, I M HCl | | | | || II 0.01 M HCl 010 . | | | | - + An electromotive force (emf) is developed in the direction shown (solution II more positive than solution I) because of the large mobility of H + compared with Cl - . A steady-state condition is quickly developed in which the tendency for H + to diffuse ahead of Cl - is counterbalanced by the potential gradient that develops. Consider an infinitesimal slice within the junction region between solutions that contains x different types of ions. 1, I 1, I 1 1, II 2, I 2, I 2 2, II x, I x, I x x, II | | | | | C C dC C | | | | | C C dC C I II | | | | | | | | | | C C dC C | | | | | + + + L L M M M M L Electrical current can be carried through the region only by the ions, where the total charge transported by a particular ion (of the j type) from left to right across the infinitesimal slice is given by = = = x 1 i i j j j j Q t F Z n Q in which n j
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 07/25/2008 for the course CEM 834 taught by Professor Mcguffin during the Fall '05 term at Michigan State University.

Page1 / 4

Handout13-ElectroPotentiaJKl - CEM 834 ELECTROCHEMICAL...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online