Calculate The Ph of A 0.035 M Strong Acid Solution.

Introduction

The pH scale measures how acidic or basic a solution is, ranging from 0 (most acidic) to 14 (most basic). For strong acids, which completely dissociate in water, the pH can be calculated directly from the concentration of hydrogen ions (H⁺).

In this guide, we'll calculate the pH of a 0.035 M strong acid solution using the pH calculation formula. We'll cover the formula, provide a worked example, and discuss how to interpret the results.

pH Calculation Formula

The pH of a strong acid solution is calculated using the following formula:

Where:

• pH is the measure of acidity
• H⁺ is the concentration of hydrogen ions in moles per liter (M)

For strong acids, the concentration of H⁺ is equal to the concentration of the acid itself, as the acid fully dissociates in water.

Worked Example

Let's calculate the pH of a 0.035 M strong acid solution step by step.

1. Identify the concentration of the strong acid: 0.035 M
2. Since it's a strong acid, [H⁺] = 0.035 M
3. Apply the pH formula: pH = -log(0.035)
4. Calculate the logarithm: log(0.035) ≈ 1.4558
5. Multiply by -1: pH ≈ 1.4558
6. Round to two decimal places: pH ≈ 1.46

The pH of a 0.035 M strong acid solution is approximately 1.46, indicating a very acidic solution.

Interpreting Results

The pH value of 1.46 indicates that the solution is strongly acidic. Here's what this means:

• pH values below 7 are acidic
• A pH of 1.46 means the solution contains 0.035 moles of hydrogen ions per liter
• This is much more acidic than common household acids like vinegar (pH ≈ 3)
• Industrial strong acids typically have pH values below 1