.. _sphx_glr_api_gallery_electrochem_standard_potentials:

Standard reduction potentials
--------------------------------

The Daniell cell from tabulated standard reduction potentials, and the
1953 Stockholm sign convention behind the table.


.. raw:: html

  <div id='sg-tag-list' class='sphx-glr-tag-list'></div>


.. raw:: html

    <div class="sphx-glr-thumbnails">

.. thumbnail-parent-div-open

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    <div class="sphx-glr-thumbcontainer" tooltip="Daniell&#x27;s 1836 two-fluid cell separated a zinc electrode in zinc (or acid) solution from a copper electrode in copper sulfate. Copper metal, not hydrogen gas, is deposited at the cathode, so the cell does not polarize. This example reproduces its standard potential with standard_cell_potential, balances the overall reaction with balance_redox_reaction, and uses the Nernst equation to show how gently the voltage falls as the cell discharges -- the steadiness that made it the first practical voltage standard.">

.. only:: html

  .. image:: /api/gallery/electrochem/standard_potentials/images/thumb/sphx_glr_plot_01_daniell_cell_thumb.png
    :alt:

  :doc:`/api/gallery/electrochem/standard_potentials/plot_01_daniell_cell`

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      <div class="sphx-glr-thumbnail-title">The Daniell cell: a steady 1.10 V from zinc and copper</div>
    </div>


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    <div class="sphx-glr-thumbcontainer" tooltip="Before IUPAC&#x27;s 1953 Stockholm meeting, one tradition tabulated oxidation potentials and another reduction potentials, so the same couple appeared with opposite signs in different books. This example shows both conventions for the table in STANDARD_REDUCTION_POTENTIALS (which follows Stockholm), and shows that the cathode-minus-anode rule of cell_potential only gives the right cell voltage and spontaneity when both half-reactions use the agreed reduction convention.">

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  .. image:: /api/gallery/electrochem/standard_potentials/images/thumb/sphx_glr_plot_02_stockholm_sign_convention_thumb.png
    :alt:

  :doc:`/api/gallery/electrochem/standard_potentials/plot_02_stockholm_sign_convention`

.. raw:: html

      <div class="sphx-glr-thumbnail-title">The 1953 Stockholm convention: electrode potentials are reduction potentials</div>
    </div>


.. thumbnail-parent-div-close

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    </div>


.. toctree::
   :hidden:

   /api/gallery/electrochem/standard_potentials/plot_01_daniell_cell
   /api/gallery/electrochem/standard_potentials/plot_02_stockholm_sign_convention