Chemistry Assignment Help with Cell Potentials
9.14 Cell Potentials (EMF) from Electrode Potentials
As mentioned at start, every galvanic cell is made up of two half cells: the oxidation half-cell (anode or negative electrode) and the reduction half-cell (cathode or positive electrode). The electrode potentials of the two half-cells of a cell differ. Due to this difference in potential, an electric current flows from the electrode at higher potential to the electrode at a lower potential. The difference in potential of the two half-cells of a cell is known as electromotive force (emf) of the cell or cell potential. It is measured directly with a voltmeter and is given in volts. Its value can also be determined by knowing the standard half-cell potentials of the two half-cells. Cell potential (or EMF of the cell) can be determined from electrode potentials in the following three ways.
(i) Cell potential (Ecell) = Reduction potential of cathode - Reduction potential of anode
In short, Ecell = Ecathode - Eanode or Ecell = Eright – Eleft
(ii) Ecell = Oxidation potential of anode - Oxidation potential of cathode
In short, Ecell = Eanode ndash; Ecathode
(iii) Ecell = Oxidation potential of anode + Reduction potential of cathode
If cell potential (Ecell) is positive, the reaction is spontaneous. Further, the more positive the value of Ecell is, the faster the reaction is. In case the value of cell potential is negative, the reaction will not take place spontaneously as written. However, the reaction will take place.
Email Based Assignment Help in Cell Potentials
We are the leading online Assignment Help provider. Find answers to all of your doubts regarding the Cell Potentials in chemistry. We at assignmenthelp.net provide homework, Assignment Help to the school, college or university level students. Our expert online tutors are available to help you in Cell Potentials. Our service is focused on: time delivery, superior quality, creativity and originality.
To Schedule a chemistry Cell Potentials tutoring session
To submit chemistry Cell Potentials assignment click here.