Definition: L'absorbance d'une solution is a measure of how much light a colored solution absorbs, ranging from 0 to 3 (dimensionless).

Vocabulary: The spectrophotomètre measures absorbance values, which are minimal for transmitted light and maximal for absorbed light.

Example: A solution showing maximum absorbance at 520 nm (green) appears magenta to the observer.

Highlight: The Beer-Lambert law states that absorbance formule A = ε × L × C, where ε is the molar absorption coefficient, L is path length, and C is concentration.

Definition: Chemical species dosing involves determining the concentration en quantité de matière in solution.

Example: Creating a calibration curve (courbe d'étalonnage absorbance en fonction de la concentration) using standard solutions of known concentrations.

Highlight: The process involves measuring absorbance at λmax, plotting the calibration curve, and using it to determine unknown concentrations.

Vocabulary: Concentration en masse relates to mass concentration (g/L), while molar concentration is expressed in mol/L.

Definition: White light spectrum encompasses all visible wavelengths from violet to red $400-800 nm$.

Vocabulary: A colored solution selectively absorbs certain wavelengths while transmitting others, resulting in the perceived color.

Example: A pure iodine solution appears green because it absorbs blue light, demonstrating the principle of complementary colors.

Highlight: The perceived color of a solution is complementary to the absorbed radiation, as shown in the chromatic circle.