For professionals working with chemical solutions, accurately determining pH is essential. This measurement, which indicates acidity or basicity, directly influences chemical and biological processes. Our pH calculator simplifies this task, providing quick and reliable results. In addition to the interactive tool, you will find a reference table with typical values for common solutions, including various types of water.
Summary
pH Calculator Parameters
The accuracy of the results depends on these elements:
- Concentration (mol/L): Define the amount of substance in the solution.
- pK: Indicates the strength of the acid/base, derived from the negative logarithm of the dissociation constant.
- Volume (L - optional): Allows dilution adjustments when necessary.
- Chemical nature: Selection between acid or base
- Ka/Kb: Specific dissociation constant for each substance
Online pH Calculator
Follow these steps to operate the calculator:
- Fill in the required fields for concentration and pK.
- Add the volume when adjustments for dilution are needed.
- Select "Acid" or "Base" and enter the corresponding value of Ka/Kb.
- Click on "Calculate pH" to get the instant result.
The system will automatically alert if essential information is missing, ensuring reliable calculations.
The pH is:
The Science of pH Explained in an Accessible Way
pH goes beyond numbers – it is a dynamic measure that influences everything from industrial reactions to biological processes. When we cook, for example, vinegar (pH ~2.5) enhances flavors by releasing H⁺ ions that modify molecular structures.
This logarithmic scale (0-14) has a critical particularity: each unit of difference represents a tenfold variation in hydrogen ion concentration. Therefore, in applications such as those listed below, precise measurement becomes essential.
- Pharmaceutical control: Medicinal enzymes require a specific pH for activation.
- Water treatment: Minimal variations affect aquatic ecosystems.
- Industrial processes: Corrosion of equipment due to excessive acidity
Reference Table: pH Values in Common Solutions
The table below provides practical guidance for quick comparisons:
These values serve as a reference but can vary depending on temperature, purity of the substances, and measurement methods. Remember that the logarithmic nature of the scale means that a seemingly small difference (e.g., pH 4 vs. pH 5) represents a concentration of H⁺ ions ten times greater. This characteristic makes precise calculation even more crucial for scientific and industrial applications.
| 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.
