## How do you calculate the mass extinction coefficient?

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According to Beer’s law, A = εbc, where A is the absorbance, ε is the molar extinction coefficient, b is the path length of the cuvette and c is the concentration. Thus, the molar extinction coefficient can be obtained by calculating the slope of the absorbance vs. concentration plot.

### What is meant by mass attenuation coefficient?

The mass attenuation coefficient is a measure of the probability of the interaction that occurs between incident photons and the matter of the unit mass per unit area.

#### What is the formula for mass coefficient?

The Mass Attenuation Coefficient, μ/ρ from which μ/ρ can be obtained from measured values of Io, I and x. Note that the mass thickness is defined as the mass per unit area, and is obtained by multiplying the thickness t by the density ρ, i.e., x = ρt.

**Why is the extinction coefficient important?**

Extinction coefficient, a measure of how strongly a substance absorbs light at a specific wavelength, is the intrinsic property of a protein depending on its composition and structure. Hence, to precisely determine protein concentration, it is fundamental to accurately determine extinction coefficient.

**How do you calculate the extinction coefficient of a protein?**

The extinction coefficient is the absorbance divided by the concentration and the pathlength, according to Beer’s Law (epsilon = absorbance/concentration/pathlength). The units of extinction coefficients are usually M-1cm-1, but for proteins it is often more convenient to use (mg/ml)-1cm-1.

## Why do we use mass attenuation coefficient?

Thus, it characterizes how easily a mass of material can be penetrated by a beam of light, sound, particles, or other energy or matter. In addition to visible light, mass attenuation coefficients can be defined for other electromagnetic radiation (such as X-rays), sound, or any other beam that can be attenuated.

### What factors affect extinction coefficient?

The three factors include: The amount of light absorbed by the substance for a specific wavelength. The distance that the light travels through the solution. The concentration of the absorbing solution per unit volume.

#### Is the extinction coefficient The slope?

Indeed the slope of your absorption spectrum would be your extinction coefficient as long as your pathlength is fixed (according to Beer-Lambert law) and you can accurately determine the concentration of each sample.