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What is pH and why importance?

What is pH and why importance?

2021-04-05

What is pH?


The term “pH” is an abbreviation for the “potential of hydrogen.” a pH is a unit of measurement which represents the concentration of hydrogen ions in a solution. This unit was introduced by biochemist Søren Peter Lauritz Sørensen in 1909. It was an easy way to represent the concentration of hydrogen ions in a solution during titrations. 


When an acid or base is added to water, that compound dissociates into ions. For acids, one of those ions is a hydrogen ion (H+) and for bases, one of the ions is a hydroxide ion (OH–). This description of acids and bases is known as the Arrhenius Theory. The concentration of hydrogen ions is often described by the pH scale as a numeric value.


Why pH is important?


pH is all around us. It is important that vital solutions such as water, stomach acid, and blood maintain a consistent pH. Water, with a neutral pH of around 7, determines the solubility of many compounds. Without the appropriate pH of water, many chemical reactions would not occur. This can also be seen through naturally occurring phenomena such as acid rain. Highly acidic precipitation can cause erosion and other hazardous environmental outcomes.


pH plays an important role in the solutions in the human body. Specific pH values are vital to the roles of solutions such as saliva, stomach acid, and blood. The production of saliva in the mouth is known as the first step of digestion. Throughout the digestive tract, food must be broken down by acidic solutions. 


It is important that the pH of saliva should be between 6.5-7.5, slightly acidic, to begin this process. Later on, stomach acid functions in the digestive system as well. It is important that stomach acid has a very acidic pH, ranging from about 1.5 to 3.5, due to the secretion of HCl and the high concentration of hydrogen ions. This strongly acidic environment kicks digestion into high gear and begins to break down food particles in preparation for the excretion process.


Healthy blood has a pH of 7.4. Hundreds of reactions occur in the bloodstream, such as enzymes, which require a specific pH. Blood with a higher or lower pH can result in negative symptoms. Acidosis is a symptom of a condition in which the pH value of blood is too low and alkalosis indicates blood with a pH value that is too high.


Humans aren’t the only organisms that rely on appropriate pH levels. Some species only thrive in alkaline (basic) environments and would not be able to survive in neutral or acidic environments. Entire ecosystems revolve around pH.


The pH Scale: Acidic, Neutral, and Basic


The pH scale describes the acidity of the solution: acidic, neutral, or basic A solution with a pH less than 7 is an acid, exactly 7 is a neutral solution, and above 7 is a base. Bases have fewer hydrogen ions but more hydroxide ions, represented by the pOH or “potential of hydroxide ions.” 


In the lab, pH can be determined by a pH indicator such as pH paper or PHS-1705 Laboratory PH Meter. In the industrial, pH can be measured by PHG-2081X Online pH meter. it’s widely used in different water applications due to precision and stability.


               
pH5806 pH Sensor

Glass material,handle 130C temperature and 6 bar pressure

               
pH8012/22 pH Sensor

pH8012 for waste water,pH80122 for pure water

               
pH8012F pH Electrode

Housing material is PTFE for corrosive application.

               
Digital pH Sensor

This pH electrode is directly RS485 Modbus for PLC

Examples of pH Values


The pH of a solution is a measure of the molar concentration of hydrogen ions in the solution and as such is a measure of the acidity or basicity of the solution. The letters pH stand for "power of hydrogen" and the numerical value for pH is just the negative of the power of 10 of the molar concentration of H+ ions. 


The usual range of pH values encountered is between 0 and 14, with 0 being the value for concentrated hydrochloric acid (1 M HCl), 7 the value for pure water (neutral pH), and 14 being the value for concentrated sodium hydroxide (1 M NaOH). It is possible to get a pH of -1 with 10 M HCl, but that is about a practical limit of acidity. At the other extreme, a 10 M solution of NaOH would have a pH of 15.

Examples of pH Values


pH of Dilute Solutions of Acids and Bases at 25 °C

[H+][OH-]pH
1.01.0 × 10-140.00
1.0 × 10-11.0 × 10-131.00
1.0 × 10-21.0 × 10-122.00
1.0 × 10-31.0 × 10-113.00
1.0 × 10-41.0 × 10-104.00
1.0 × 10-51.0 × 10-95.00
1.0 × 10-61.0 × 10-86.00
1.0 × 10-71.0 × 10-77.00
1.0 × 10-81.0 × 10-68.00
1.0 × 10-91.0 × 10-59.00
1.0 × 10-101.0 × 10-410.00
1.0 × 10-111.0 × 10-311.00
1.0 × 10-121.0 × 10-212.00
1.0 × 10-131.0 × 10-113.00
1.0 × 10-141.0 14.00


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