Although Lambert did not claim a discovery, it has often been attributed. August Beer discovered a related law in 1852. The Beer Act states that absorption is proportional to the concentration of the sample. Technically, the Beer Act refers only to concentration, while Lambert`s Beer Law refers to absorption at both the concentration and thickness of the sample. Bier`s law is an equation that relates the attenuation of light to the properties of a material. The law states that the concentration of a chemical is directly proportional to the absorption of a solution. The relationship can be used to determine the concentration of a chemical species in a solution using a colorimeter or spectrophotometer. The relationship is most often used in UV-visible absorption spectroscopy. Note that the beer law is not valid for high concentrations of solution.
It is a common observation that when we direct a beam of light through a solution, its intensity decreases. For example, when we children direct our laser lights or flashlights through a glass of milk or juice, we could barely see a light on the other side of the glass. Another naturally observed example is the transmission of solar radiation (light) through the atmosphere. The intensity of solar radiation emitted by the sun weakens as it passes through the Earth`s atmosphere, which is good news for us! In general, Bier`s law and Lambert`s law are generally considered Lambert`s law in combination because they can determine the absorption relationship with the length of the path of light in the sample and the concentration of the sample. The main difference between Bier`s law and Lambert`s law is that the law of beer states that the amount of light absorbed is proportional to the concentration of the solution, while Lambert`s law states that the absorption and length of the path are directly proportional. The main difference between Bier`s law and Lambert`s law is that the law of beer states that the amount of light absorbed is proportional to the concentration of the solution, while Lambert`s law states that the absorption and length of the path are directly proportional. Lambert noted in his book Photometria that the absorption of light from a sample is directly proportional to the length or thickness of the sample (solution) through which the light passes. More than 120 years later, in 1852, August Beer found a different correlation for decreased light intensity. He explained that «the amount of light absorbed by a solution, or the absorption of a solution, is directly proportional to its concentration.» For the sake of the law of beer, we assume that light is absorbed only by any of the other optical events. The value of ΔI then corresponds to the amount of light absorbed by the solution (ΔI = I absorbed). In reality, the amount of light absorbed is calculated by passing the light through two different solutions – one containing only the solvent and the other in which the solute (attenuation species) is dissolved.
The Beer Act states that the absorption of light from a solution is directly proportional to the concentration of damping species and the length of the optical path. However, if the law on beer states that the amount of light absorbed is proportional to the concentration of solution, two hypotheses must be taken into account when calculating: the law may have «beer» in its name, but it is actually red wine that led Pierre Bouguer to discover a key element of this law. Pierre Bouguer, a French mathematician, was sipping red wine while on vacation in Alentejo, Portugal, in 1729, when he invented half of the beer law. However, Johann Heinrich Lambert is often credited with the complete discovery, although he was only the one who quoted it in Bouguer`s Optical Essay on the Gradation of Light. Does the Beer Act apply to beer? Now that you know everything about the law, why not find out for yourself the next time you go out with your friends for a few weekend eyebrows? Lambert`s law states that the absorption of a sample is directly proportional to the length of the path of light in that sample. Usually, this law is used in combination with the Beer Act, which is then called the Beer-Lambert Act. Indeed, the Beer-Lambert law is very useful in spectroscopic analysis other than these individual laws. Lambert`s law was first introduced by Johann Heinrich Lambert. The law of beer and Lambert`s law are usually taken in combination with Lambert`s law of beer, as they can indicate the absorption relationship with both the length of the path of light in the sample and with the concentration of the sample. While many modern instruments perform Beer`s law calculations by simply comparing an empty bowl to a sample, it is easy to create a diagram with standard solutions to determine the concentration of a sample.