pH
WHAT IS IT?
About pH
pH, commonly used for water measurements, is a measure of acidity and alkalinity, or the caustic and base present in a given solution. It is generally expressed with a numeric scale ranging from 0-14. The value 7 represents neutrality. The numbers on the scale increase with increasing alkalinity, while the numbers on the scale decrease with increasing acidity.
Each unit of change represents a tenfold change in acidity or alkalinity. The pH value is also equal to the negative logarithm of the hydrogen-ion concentration or hydrogen-ion activity. pH values for some common solutions are listed in the table to the right.

Preparing chemical solutions?
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How Are pH Measurements Used?
pH measurements are widely used to control processes, ensure product quality and safety.
Custom pH Sensor Design and Manufacturing
In addition to our standard products, Sensorex designs and manufactures pH sensors for over 250 OEM partners. Whether you are looking to private label sensors and instrumentation or incorporate pH sensors as part of the design for your water treatment product, our team of engineers and application specialists can help you meet your goals. We provide custom branding on our standard products and can design custom pH sensors to meet various design specifications.

Popular ProductsSensorex pH Best Sellers
TX100 pH/ORP Loop Powered 4-20mA Transmitter
Our TX100 is a fully-featured ORP/pH transmitter for use with pH and ORP sensors. The large display shows pH/ORP value simultaneously with…
pH Buffer Solutions
Sensorex pH buffer solutions are used for calibration of pH sensors. Buffers are color coded for (red) 4.01. (Yellow) 7.00 and (blue) 10.00.…
S8000CD – pH Sensor Cartridge for S8000 Series pH Kits, Quick Change
Our S8000 series of pH deliver the most reliable online pH monitoring in a unique, modular package that minimizes total…
S651CD – pH Electrode, Flat-Surface, Submersible
This submersible pH electrode is ideal for tanks, flumes and sewer lines. Three versions available: general purpose, HF-resistant, or low-conductivity…
pH2000 – pH Sensor, Laboratory, Extended Life
Applications such as environmental and wastewater sampling involve some uncertainty about what samples may contain. When dealing with unknown or unpredictable sample…
S272CD – Process pH Sensor
The S272CD online process pH sensor delivers reliable online monitoring for in-line or submersion installation configuration. This sensor is designed…
S656CD – pH Sensor Cartridge (Hot Tap, Insertion)
Users installing into large tanks, large process lines and scrubber lines will appreciate this flat surface self cleaning hot tap…
pH1600 – Laboratory pH Electrode
The Sensorex pH1600 is one of our most popular laboratory pH electrodes, due to its reliability and low maintenance design.…
Shop NowMore from Sensorex
In addition to pH sensors we have a full range of water quality sensors.
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