The pH Calculator is a useful tool for anyone working with chemical solutions who needs to measure the pH of a solution. pH is a measure of the acidity or basicity of a solution and is important for many chemical and biological processes. On this page you will also find a PH table of common solutions such as water of different types.
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pH Calculator Parameters
The pH calculator we created is based on a few simple parameters that the user must input to get the pH of the solution. The parameters are:
- Concentration – The concentration of the solution in mol/L (molarity).
- pK – The pK of the chemical species involved in the acid-base reaction. The pK is the negatively transformed acid or base dissociation constant to logarithm to base 10.
- Volume – The volume of the solution in liters (L).
- Acid/Base – Whether the chemical species involved in the acid-base reaction is an acid or a base.
- Ka/Kb – The acidic or basic dissociation constant of the chemical species involved in the acid-base reaction.
Online pH Calculator
To use the calculator, follow these steps:
- Enter the concentration of the solution in mol/L in the Concentration field.
- Enter the pK of the chemical species involved in the acid-base reaction in the pK field.
- (Optional) Enter the volume of the solution in liters in the Volume field.
- If the chemical species involved in the acid-base reaction is an acid, select “Acid” in the Acid/Base field and enter the acid dissociation constant in the Ka field. If it is a base, select “Base” in the Acid/Base field and enter the basic dissociation constant in the Kb field.
- Click the “Calculate pH” button and the pH of the solution will be displayed in the “The pH is” field.
The pH is:
Explanation
- In addition to the mandatory fields for concentration and pK, there are optional fields for volume, acid/base, Ka, and Kb.
- If the user selects “Acid” or “Base” in the Acid/Base field and fills in the Ka or Kb field, the calculator will use the corresponding formula to calculate the pH.
- If the user fills in the Volume field, the pH is adjusted by the equation pH = pH – log[V].
- If the user does not fill in all required fields, the calculator displays a warning message and returns without calculating the pH.
What is pH? Understanding the pH
pH is a very important measurement in chemistry and biology, but it can often be difficult to understand. Let's try to explain this in a fun and easy to understand way.
Imagine you are cooking a delicious meal and you need to add some acid to enhance the flavor. You add a few drops of lemon juice to your food and are surprised to find that it tastes better. But why did this happen?
Lemon juice is acidic and contains molecules called hydrogen ions. These hydrogen ions are responsible for the sour taste of lemon juice. When you add lemon juice to your food, the hydrogen ions in the juice interact with the molecules in the food. This interaction can change the structure of the food molecule and, as a result, alter the taste.
The measure of the number of hydrogen ions in a solution is called the pH. The pH is a scale from 0 to 14 and indicates whether a solution is acidic, neutral or basic. A solution with a pH below 7 is considered acidic, a solution with a pH 7 is neutral, and a solution with a pH above 7 is basic.
pH is important because many chemical and biological reactions are sensitive to pH. For example, our body's enzymes, which are responsible for accelerating chemical reactions, only work within a certain pH range. If the pH is outside this range, enzymes can become inactivated and chemical reactions can be affected.
Another example is pool water. When pool water is too acidic, it can corrode equipment and irritate swimmers' skin. When pool water is too basic, it can create limescale deposits and cause problems with water filtration.
It is therefore important to measure the pH of solutions and keep the pH within the correct range to ensure that chemical and biological reactions occur correctly. I hope this explanation was fun and easy to understand!
Already calculated pH table - Common Values
Here is a table with some common pH values for different solutions:
| Substance | pH |
|---|---|
| Pure water | 7,0 |
| human blood | 7,35 – 7,45 |
| concentrated hydrochloric acid | < 0.0 |
| Gastric juice | 1,0 – 3,0 |
| pancreatic juice | 8,0 – 8,3 |
| Acetic acid (vinegar) | 2,4 – 3,4 |
| Refrigerator | 2,5 – 4,0 |
| Sea water | 7,5 – 8,4 |
| pool water | 7,2 – 7,8 |
| Milk | 6,5 – 6,8 |
| Liquid soap | 9,5 – 10,5 |
| Ammonia | 11,0 – 12,0 |
| Sodium bicarbonate | 8,2 |
| Coke | 2,5 |
| Milk of magnesia | 10,5 – 11,5 |
| Buffer solution pH 4.00 | 4,00 |
| Buffer solution pH 7.00 | 7,00 |
| Buffer solution pH 10.00 | 10,00 |
| Red wine | 3,5 |
| Bleach (sodium hypochlorite) | 11,0 – 13,0 |
| Phosphoric acid | 2,1 – 2,3 |
| concentrated sulfuric acid | < 0.3 |
| Lemon juice | 2,0 |
| Sparkling water | 4,5 – 5,0 |
| Distilled water | 5,0 – 7,0 |
| ammonium bicarbonate | 7,8 |
| Chloroquine (0.05% solution) | 8,4 |
| Sodium hydroxide (caustic soda) | 14,0 |
| Cow milk | 6,4 – 6,8 |
| Honey | 3,9 |
| Neutralization of HCl with NaOH | 7,0 |
| Neutralization of HCl with NH4OH | 5,0 |
| Neutralization of H2SO4 with NaOH | 7,0 |
| Neutralization of H2SO4 with NH4OH | 4,0 |
| bird blood | 7,8 |
| mammalian blood | 7,4 |
These values are just a guide and may vary depending on many factors such as temperature and solution concentration. It is important to remember that pH is a logarithmic measure, which means that a one-unit change in pH represents a 10-fold change in the acidity or basicity of the solution. So even a small change in pH can have a big impact on the chemical or biological reaction taking place.
