Portable Glass Electrode pH Meter

Equilibrium Potentials of Membrane Electrodes ( glass electrode / pH ) JUI

A simple thermodynamic theory of the equilibrium potentials of membrane electrodes is formulated and applied to the glass electrode for measurement of pH. The new formulation assumes the selective adsorption or binding of specific ions on the surface of the membrane which may or may not be permeable to the ion, and includes the conventional derivation based on reversible ion transport across me...

pH Measurement with the Glass Electrode and Vacuum Tube Potentiometer.

Development of the Glass Electrode and the pH Response

The glass electrode is the most commonly used device to access the pH of an aqueous solution. It attains highly accurate measurements via simple and well-established procedures. However, the reasons why the glass electrode potential scales with hydrogen ion concentration according to almost Nernstian potential values have been long-standing challenges to explain. Only in the past 50 years has a...

The Youden pH Meter

Sørensen used a slide-wire potentiometer to make his pH measurements. Here a known potential is applied to counterbalance the potential of the hydrogen cell (i.e. the hydrogen electrode plus the counter electrode) and to reduce its current output to zero, at which point the value of the applied counter-potential is equal to that of the cell potential. Since the point of balance is indicated by...

A GLASS ELECTRODE APPARATUS FOR MEASURING THE pH VALUES OF VERY SMALL VOLUMES OF SOLUTION

A glass electrode apparatus is described with which pH measurements can be made with as small volumes as 2 drops (about 0.14 cc.) of solution. Using this apparatus the change of pH of the vacuolar sap of Nitella, due to the penetration of brilliant cresyl blue, has been readily followed. The sap and the dye have been found to poison the usual type of hydrogen electrode.