What is the principle of operation of the pH electrode?
What is the principle of operation of the pH electrode?
A pH meter is a scientific instrument that measures the hydrogen-ion activity in solutions, indicating its acidity or basicity (alkalinity) expressed as pH value. The principle of pH meter is the concentration of hydrogen ions in the solution e.g. it is the negative logarithm of an hydrogen ion.
Who invented pH electrode?
Arnold O. Beckman
Over 60 years ago, Arnold O. Beckman invented the world’s first pH meter, initiating a long and distinguished career as a businessman, philanthropist, and inventor of scientific instruments.
How accurate is a pH electrode?
Most manufacturers of pH electrodes build to a quality level that gives an accuracy of approximately 0.1 pH. If the pH sensor is properly maintained, calibrations done correctly, and stored according to manufacturer recommendations, then 0.1 is possible.
What is pH meter biotechnology?
pH meter is a potentiometer that measures the voltage between two electrodes dipped in a solution. One of these electrodes is a calomel electrode and the other a glass electrode.
Who invented the first pH meter?
Arnold O. Beckman developed the first commercially successful electronic pH meter while a member of the faculty of the California Institute of Technology. This rugged and portable “acidimeter,” which had all necessary components housed in a single unit, allowed scientists to measure acidity accurately and rapidly.
Why are pH meters so inaccurate?
The pH meter and all its electrical connections should have high insulation resistance as short circuits can cause errors in the pH reading and damage the instrument. Thus, only coaxial cables are used in pH meters and the connecting cables have a semiconducting layer apart from the copper shielding.
What is the most common error in pH measurement?
temperature
The most common cause of error in pH measurements is temperature. The slope of a pH electrode is highly dependent of temperature, and pH buffer values and sample values change with temperature.
What is the full name of pH?
potential of hydrogen
The letters pH stand for potential of hydrogen, since pH is effectively a measure of the concentration of hydrogen ions (that is, protons) in a substance. The pH scale was devised in 1923 by Danish biochemist Søren Peter Lauritz Sørensen (1868-1969).
What is potentiometer Slideshare?
Working At its most basic, a potentiometer consists of two electrodes, whose reduction potentials differ, inserted in a test solution. The voltmeter is attached to the electrodes to measure the potential difference between them. One of the electrodes is a reference electrode, whose electrode potential is known.
What is pH electrode theory?
pH Electrode Theory pH electrode measurements are made by comparing the readings in a sample with the readings in standards whose pH has been defined (buffers). When a pH sensing electrode comes in contact with a sample, a potential develops across the sensing membrane surface and that membrane potential varies with pH.
How do I choose the right pH electrode for my application?
Electrode types, features, and compatibility are determining factors in selecting the right pH electrode. pH electrodes are available with a glass or epoxy body and a variety of electrode body styles, fill types, references, junctions, and connectors to suit your application.
What is the range of a glass electrode pH scale?
Its range is 4 to 11.5 pH and, although quite rugged, is subject to error. The glass electrode, which consists of a thin wall glass bulb (sometimes as little as 1 micron thick) and is made of a critically composed glass, has an extremely high resistance (2 to 6 megohms) so that galvanometers of comparable sensitivity are required.
Does Thermo Scientific have an electrode for my application?
Regardless of how simple or complex your application, Thermo Scientific has an electrode that can meet your needs. Select from the applications below to view suggested electrodes from our extensive portfolio for each category.
