pH Base Fraca
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
base fraca
About this calculator
The pH Weak Base Calculator calculates the acid-base ratio (pH) of a solution based on the acid dissociation constant (pKb) and the concentration (C).
This formula is useful for determining the pH of a weak base in different concentrations. It is especially important in situations where the concentration of the base is known, but the pH is unknown.
Note that this calculator uses the formula pH = 14 − ½·(pKb − log C). Make sure you are using the correct unit for the pKb and the concentration (C).
Caution: this calculation is valid only for ideal solutions and under static conditions. In real-world situations, other factors such as temperature, pressure, and the presence of impurities may affect the pH.
Frequently asked questions
What is a weak base?
A weak base is a substance that does not completely react with water to form hydroxide ions. It is different from a strong base, which completely reacts with water.
Why is it important to calculate the pH of a weak base?
Calculating the pH of a weak base is important because it can affect the safety and effectiveness of a chemical reaction. Additionally, it can help predict the formation of toxic or corrosive substances.
What are the correct units for pKb and concentration (C)?
The correct units for pKb are pH and for concentration (C) are M (mole/liter). Make sure to use these units to get accurate results.
Is this calculator valid for all situations?
No, this calculator is valid only for ideal solutions and under static conditions. In real-world situations, other factors can affect the pH.
How should I use this calculator?
Use this calculator to calculate the pH of a weak base in different concentrations. Make sure you have basic knowledge of chemistry and use the correct units.