If you are conducting any research that involves measuring the pH of a substance, you will need an appropriate pH measurement device. This is done through the use of a pH electrode and meter that shows how acidic a solution is on the pH scale. Being able to measure the pH of a sample has a range of implications depending on the research conducted. So, what exactly is pH measurement and what do we use it for? Here is a brief rundown of the pH meaning and why we need to measure it.

What is pH?

In chemistry, pH stands for the potential (or power) of Hydrogen (H+). pH is usually measured in aqueous solutions, but not exclusively. In aqueous samples, water (H₂O) dissociates into hydrogen ions, symbolised H+, and hydroxide ions, symbolised OH-. The ratio in which these ions exist in the sample will determine the acidity or alkalinity. At acidic pH there is an excess of hydrogen ions in a solution, and as we move up the scale towards the alkaline side, there is an excess of hydroxide (OH-) ions.

The pH scale is a logarithmic scale that measures the overall acidity or alkalinity of a substance. Each unit change in the scale corresponds to a tenfold change in the balance of H+ or OH- ions. The scale ranges from 0 (very acidic) to 14 (very alkaline), with 7 being a neutral value. As an example, lemon juice and vinegar are highly acidic with a pH of around 2, while soap and bleach have highly alkaline pH of around 12 or 13. pH measurement can be conducted with a pH electrode and reference electrode (which are often both housed into one body in a combination electrode). The combination electrode is connected to a pH meter, which measures the constant voltage from the reference electrode, and the variable voltage from the measuring (pH) electrode which is sensitive to hydrogen ions, and displays the value in pH units.

The Importance of pH Measurement

There are many reasons why measuring pH is important in a range of industries:

• Manufacturing- In a variety of manufacturing settings, pH measurement can ensure reproducibility and quality of products.
• Water Industries – It is important to measure the pH of water, including wastewater, drinking water, and natural water sources such as lakes and oceans. This helps avoid pollution that could harm the environment, people or wildlife.
• Swimming Pools – pH of swimming pool water is monitored and kept to a neutral or slightly alkaline pH to prevent skin irritation. Checking the pH can also help prevent common maintenance problems.
• Medicine – There are many medical and pharmaceutical uses for pH electrodes, including ensuring a precise pH for bacterial growth, or checking pH of medicinal products to ensure they are safe for human consumption.
• Cosmetics – Determining the pH levels of cosmetic products can give information about quality and safety.
• Food Production – Measuring pH allows producers to find the optimum level for the best quality produce as well as making sure public health is maintained. There are many different food applications in which pH electrodes are used, for example dairy products, fruit, vegetables, bread, pickled products and many more.
• Beverages – pH is an important measure in the beverage industry, including wine production, brewing, fruit juice production and many more. It can help ensure that the product is reproducible and maintains taste and quality.

Sentek for pH Measuring Products

At Sentek we have a wide range of pH testing products available for whatever field of research you are in. Visit our online store for our range of pH electrodes, sensors and other accessories. For the best in pH measurement contact Sentek today.