PH meter

pH electrodepH-metermeterpHpH electrodespH measurementspH probepH probes
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH. The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode, and so the pH meter is sometimes referred to as a "potentiometric pH meter".wikipedia
114 Related Articles

PH

pH levelneutralpH value
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH.
The pH of aqueous solutions can be measured with a glass electrode and a pH meter, or a color-changing indicator.

Glass electrode

pH glass electrodeminiature pH electrodepH-electrode
It usually has a glass electrode and a reference electrode, or a combination electrode.
Glass electrodes are commonly used for pH measurements.

Silver chloride electrode

silver/silver chlorideAg-AgClAgCl
The silver chloride electrode is most commonly used as a reference electrode in pH meters, although some designs use the saturated calomel electrode.
For example, it is usually the internal reference electrode in pH meters and it is often used as reference in reduction potential measurements.

Arnold Orville Beckman

Arnold O. BeckmanArnold BeckmanArnold and Mabel Beckman
In October 1934, Arnold Orville Beckman registered the first patent for a complete chemical instrument for the measurement of pH, U.S. Patent No.
While a professor at California Institute of Technology, he founded Beckman Instruments based on his 1934 invention of the pH meter, a device for measuring acidity, later considered to have "revolutionized the study of chemistry and biology".

Beckman Coulter

Beckman InstrumentsHybritechNational Technical Laboratories
On April 8, 1935, Beckman's renamed National Technical Laboratories focused on the manufacture of scientific instruments, with the Arthur H. Thomas Company as a distributor for its pH meter.
Founded by Caltech professor Arnold O. Beckman in 1935 as National Technical Laboratories to commercialize a pH meter that he had invented, the company eventually grew to employ over 12,000 people, with $5.8 billion in annual sales by 2017.

PH indicator

indicatorindicatorschemical indicator
There are also holographic pH sensors, which allow pH measurement colorimetrically, making use of the variety of pH indicators that are available.
For applications requiring precise measurement of pH, a pH meter is frequently used.

Saturated calomel electrode

SCEcalomel electrodeHg 2 Cl 2
The silver chloride electrode is most commonly used as a reference electrode in pH meters, although some designs use the saturated calomel electrode.
The SCE is used in pH measurement, cyclic voltammetry and general aqueous electrochemistry.

Radiometer (company)

Radiometer
The Radiometer Corporation of Denmark was founded in 1935, and began marketing a pH meter for medical use around 1936, but "the development of automatic pH-meters for industrial purposes was neglected. Instead American instrument makers successfully developed industrial pH-meters with a wide variety of applications, such as in breweries, paper works, alum works, and water treatment systems."
This soon resulted in the first commercially available pH meter.

National Historic Chemical Landmarks

National Historic Chemical LandmarkInternational Historic Chemical LandmarkACS National Historic Chemical Landmark
In 2004 the Beckman pH meter was designated an ACS National Historic Chemical Landmark in recognition of its significance as the first commercially successful electronic pH meter.

California Institute of Technology

CaltechCalifornia Institute of Technology (Caltech)Cal Tech
Beckman developed the prototype as an assistant professor of chemistry at the California Institute of Technology, when asked to devise a quick and accurate method for measuring the acidity of lemon juice for the California Fruit Growers Exchange (Sunkist).
Arnold Beckman (PhD 1928) invented the pH meter and commercialized it with the founding of Beckman Instruments.

ISFET

ion-sensitive field-effect transistorreference ISFETion-sensitive
Additionally, there are commercially available pH meters based on solid state electrodes, rather than conventional glass electrodes.

Scientific instrument

scientific instrumentsinstrumentanalytical instruments
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH.

Hydrogen ion

H + Hhydrogen ions
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH.

Thermodynamic activity

activityactivitieschemical activity
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH.

Aqueous solution

aqueouswater solubilityaqueous solutions
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH.

Acid

acidicacidityacids
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH.

Alkalinity

alkalinealkalictotal alkalinity
A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH.

Experiment

experimentalexperimentationexperiments
The pH meter is used in many applications ranging from laboratory experimentation to quality control.

Quality control

quality standardsqualityquality standard
The pH meter is used in many applications ranging from laboratory experimentation to quality control.

Laboratory

laboratorieslaboratory equipmentlab
Knowledge of pH is useful or critical in many situations, including chemical laboratory analyses.

Soil

soilsdirtsoil moisture
pH meters are used for soil measurements in agriculture, water quality for municipal water supplies, swimming pools, environmental remediation; brewing of wine or beer; manufacturing, healthcare and clinical applications such as blood chemistry; and many other applications.

Agriculture

farmingagriculturalAgriculturist
pH meters are used for soil measurements in agriculture, water quality for municipal water supplies, swimming pools, environmental remediation; brewing of wine or beer; manufacturing, healthcare and clinical applications such as blood chemistry; and many other applications.

Water quality

qualitywaterchemical hydrology
pH meters are used for soil measurements in agriculture, water quality for municipal water supplies, swimming pools, environmental remediation; brewing of wine or beer; manufacturing, healthcare and clinical applications such as blood chemistry; and many other applications.

Tap water

running waterindoor plumbingmunicipal water
pH meters are used for soil measurements in agriculture, water quality for municipal water supplies, swimming pools, environmental remediation; brewing of wine or beer; manufacturing, healthcare and clinical applications such as blood chemistry; and many other applications.

Swimming pool

poolswimming poolspools
pH meters are used for soil measurements in agriculture, water quality for municipal water supplies, swimming pools, environmental remediation; brewing of wine or beer; manufacturing, healthcare and clinical applications such as blood chemistry; and many other applications.