Introducing an intuitive and user-friendly hydrogen ion concentration calculator designed to assist you in determining the hydrogen ion concentration [H+] based on the solution’s pH. Understanding pH is crucial for identifying whether a solution is acidic or basic. Explore the text below to grasp the pOH formula and learn how to calculate pH from the pOH scale.

### What is a Hydrogen Ion?

A hydrogen ion, denoted as H+, is commonly known as a proton. In water, molecules can dissociate into hydrogen ions (H+) and hydroxide ions (OH-):

H2​OH++OH

Additionally, you may encounter the notation H3O+, representing a hydronium ion, which is essentially a water molecule (H2O) combined with a hydrogen ion (H+).

In solution, acids break down into H+ and an anion:

HAH++A

Similarly, alkalis produce an ion and OH-:

BOHB++OH

### Relationship Between Hydrogen Ions and pH

The hydrogen ion concentration forms the basis of the pH scale, where the number of hydrogen ions determines the solution’s acidity or basicity. An acid, producing H+ ions, results in a solution with a lower pH. The pH scale ranges from 0 to 14, with values below 7 indicating acidity, 7 for neutrality (pure water), and values above 7 indicating basicity. The pH scale operates logarithmically, meaning each unit change signifies a tenfold difference in hydrogen ion concentration.

### Calculating Hydrogen Ion Concentration from pH

To find the hydrogen ion concentration [H+] from a given pH, utilize the formula:

[H+]=10−pH

For instance, a solution with a pH of 6.5 corresponds to a hydrogen ion concentration of 3.16 × 10^-4 mol/L. This calculator allows you to input pH, pOH, or hydrogen ion concentration to obtain the other quantities.

### pOH Formula

The pOH scale complements pH and helps determine a solution’s acidity or alkalinity. The pOH can be calculated as the negative logarithm of the hydroxide ion OH- concentration:

pOH=−log([OH−])

At 25 °C, pH and pOH are related by the equation pH+pOH=14.

### How to Use the Hydrogen Ion Concentration Calculator

Suppose you have a solution with a pH of 3.5 and want to find the [H+] concentration. Follow these steps:

1. Enter the pH value (e.g., 3.5) into the “pH” field.
2. The [H+] ion concentration is calculated as 3.16 × 10^-4 mol/L.
3. Check the pOH value (e.g., 10.5).

You can enter any known value—pH, pOH, or hydrogen ion concentration—and the calculator will compute the other quantities.