What does the pH represent.The effect of the pH on the water

pH value generally refers to the hydrogen ion concentration index, then the pH value represents the hydrogen ion concentration index.
When the pH value is higher than 7, the aqueous solution is alkaline, and the higher the pH value, the stronger the alkaline; When the pH value is lower than 7, the aqueous solution is acidic, and the lower the pH value, the stronger the acidity; When the pH value is equal to 7, the aqueous solution is neutral.
Hydrogen ion concentration index (English hydrogenionconcentration; French potentield'hydrogène) refers to the ratio
of the total number of hydrogen ions in a solution to the amount of total substance.

It is generally referred to as "pH", not "pH"
.

Indicates the value of the pH of the solution, pH = -lg[H+] is the negative value
of the commonly used logarithm of the concentration of hydrogen ions contained.

The determination of hydrogen ion concentration index can be mainly determined by using pH indicators, pH test strips, and pH meters
.

3.
pH value is one of the most important physicochemical parameters of
an aqueous solution.

Where natural phenomena
involving aqueous solutions.

Chemical changes and production processes are all related to pH, so pH values need to be measured in industrial, agricultural, medical, environmental and scientific fields
.

4.
The pH value of water is a negative log value of the hydrogen ion activity in the water, which is expressed as: pH = -lg [H⁺] 5.
pH value is sometimes called hydrogen ion index, because the value of hydrogen ion concentration is often very small, it is very inconvenient in application, so the concept of pH value is used as a judgment index
for the acidity and alkalinity of aqueous solutions.

Moreover, the negative logarithmic value of hydrogen ion activity can indicate the magnitude of the magnitude of the change in acidity and alkalinity, so that it is very convenient to apply, and thus (at 25 °C): 6.
(1) neutral aqueous solution, pH = 7 (2) acidic aqueous solution, c(H⁺)>c (OH⁻), pH <7, the smaller the pH value, the stronger the acidity; (3) alkaline aqueous solution, c(H⁺)<c(OH⁻), pH>7, the greater the pH value, the stronger
the alkaline.

7.
At standard temperature (25 ° C) and pressure, the aqueous solution pH = 7 (such as: pure water) is neutral, this is because the product of the concentration of hydrogen ions and hydroxide ions naturally ionized by water at standard temperature and pressure (the ion product constant of water) is always 1×10⁻¹⁴, and the concentration of both ions is 1×10⁻⁷mol/L
.

A small pH value indicates that the concentration of H⁺ is greater than the concentration of OH⁻, so the solution is highly acidic, while the increase in pH value indicates that the concentration of H⁺ is less than the concentration of OH⁻, so the solution is strong
.

Therefore, the smaller the pH value, the stronger the acidity of the solution; The higher the pH, the more
alkaline the solution.

8.
Usually the pH value is a number between 0 and 14 (concentrated sulfuric acid pH is about -2), at a temperature of 25 ° C, when the pH < 7, the solution is acidic, when the pH > 7, the solution is alkaline, when the pH = 7, the solution is neutral.
However, under non-aqueous solutions or non-standard temperatures and pressures, pH = 7 may not mean that the solution is neutral, which requires the pH neutral value
to be determined by calculating the ionization constant of the solvent under such conditions.

For example, at a temperature of 373K (100 ° C), pH = 6 is a neutral solution
.

This time recommended for everyone is a PH online monitoring instrument - PHG-2091 of Shanghai Bozhi Instrument