Absorbance refers to the amount of light absorbed by a substance when it interacts with electromagnetic radiation. It is commonly measured using a spectrophotometer or colorimeter to determine the concentration of a solute in a solution based on the Beer-Lambert Law.
Think of absorbance like sunglasses for light - substances can "put on" different shades (absorb different wavelengths) depending on their concentration.
Transmittance: The amount of light that passes through a substance without being absorbed or scattered.
Wavelength: The distance between two consecutive peaks or troughs in an electromagnetic wave; different colors have different wavelengths.
Spectrophotometer: An instrument used to measure the intensity of light at specific wavelengths, allowing scientists to analyze absorption spectra.
An analyte at a concentration of 5.0x10^-3 M gives an absorbance of 0.50 at a specific wavelength and a cell path length of 1.00 cm. What is the molar absorptivity?
The absorbance of an iron thiocyanate solution containing 0.005 mg Fe/mL was reported as 0.490 at 540 nm. Calculate the specific absorptivity under the assumption that a 1.00 cm cuvette was used.
The absorbance of an iron thiocyanate solution containing 0.005 mg Fe/mL was reported as 0.490 at 540 nm. What will be the absorbance if the solution is diluted to twice its original volume?
A solution containing 40.00g/L of a substance had an absorbance of 0.425 in a 1.00 cm cell at 690 nm. If 5.00 mL of this solution was diluted with water to 100.0 mL, what is the absorbance of the new solution at 690 nm?
Copper sulfate creates an extraordinarily blue solution in water. Which of the following experimental techniques could a scientist use to determine the concentration of copper sulfate based on absorbance?
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