1. What is a Concentration of Solution Calculator?

Definition: This calculator estimates the concentration of a solution based on its absorbance, cell thickness, and molar extinction coefficient.

Purpose: It helps chemists and researchers determine solution concentrations using spectrophotometry measurements.

2. How Does the Calculator Work?

The calculator uses Beer-Lambert's Law:

Where:

• \( c \) — Concentration of solution (mol/m³)
• \( A \) — Absorbance (unitless)
• \( l \) — Thickness of cell (m)
• \( \epsilon \) — Molar extinction coefficient (m²/mol)

Explanation: The absorbance is divided by the product of path length and molar absorptivity to determine concentration.

3. Importance of Concentration Calculation

Details: Accurate concentration measurements are essential for chemical analysis, quality control, and research experiments.

4. Using the Calculator

Tips: Enter the absorbance value, cell thickness (default 0.00000005 m), and molar extinction coefficient (default 0.0019 m²/mol). Thickness and coefficient must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is absorbance?
A: Absorbance is a measure of how much light a solution absorbs at a specific wavelength, measured by a spectrophotometer.

Q2: What's a typical cell thickness?
A: Standard cuvettes typically have a 1 cm (0.01 m) path length, but micro cells can be much smaller (e.g., 50 nm).

Q3: How do I find the molar extinction coefficient?
A: The coefficient is specific to each substance and wavelength, often found in chemical literature or determined experimentally.

Q4: What units does this calculator use?
A: Concentration is in mol/m³ (SI units). For mol/L, divide the result by 1000.

Q5: What are the limitations of this calculation?
A: The Beer-Lambert law assumes dilute solutions and no chemical interactions that might affect absorbance.