A Graduated Cylinder Colorimeter: An Investigation of Path Length and the Beer-Lambert Law

Abstract

A 10-mL graduated cylinder was used to construct a colorimeter to investigate the relationship between absorbance and path length found in the Beer-Lambert law. Light-emitting diodes (LEDs) were used as the light sources and filter monochromators. The experiments were conducted on intensely colored permanganate and tetraamminecopper(II) solutions. The device also was useful for demonstrating the relationship between absorbance and concentration.

Open-source colorimeter assembled from laser-cut plates and plug-in circuits

“…Taking into account the minimum increment of the output values from the colorimeter, the measurement resolution is 0.01 for absorbances less than 1. Compared to previous reports, in which some studies have only attempted measurements of absorbance up to 0.5 [6,7,11,12,18], while others have shown the linearity even at absorbance greater than 1 [8,10,19,20], the performance of our colorimeter was superior to or comparable to that of the previous handmade colorimeters.…”

“…Because of its simple structure, colorimeters are often made in a classroom by students themselves. The most inexpensive and simple handmade colorimeter consists of a monochromatic LED as a light source and a cadmium sulfide (CdS) photoresistor as a light detector, which are placed in a cardboard or plastic enclosure [6,7]. Since the CdS decreases the electrical resistance with respect to the luminosity, the change in light intensity can easily be determined by measuring the resistance of the CdS with a voltmeter.…”

Investigation on the effects of water loss on the solar spectrum reflectance and transmittance of Osmanthus fragrans leaves based on optical experiment and PROSPECT model

“…According to Lambert–Beer's law, the absorption of light by a solution is proportional to the depth of the solution layer and the concentration of the solution: 30 log( I 0 / I t ) = k s lc = A where I 0 and I t are the incident radiation and transmitted radiation, k s is the absorption coefficient, l , c and A are the depth, concentration and absorbance of the supernatant solution, respectively. The concentrations of chlorophyll a, c a , chlorophyll b, c b , and carotenoids, c car , in the supernatant solution can be determined via ref.…”

Synthesis of two nickel (II) complexes bearing pyrrolide-imine ligand and their catalytic effects on thermal decomposition of ammonium perchlorate

“…With this method, quartz material was used as cuvette, whose volume was 1.0 × 1.0 × 4.0 cm 3 . The extinction coefficient was calculated according to Lambert-Beer's law [43].…”