Basicallu the question is asking how we can find the concentration of a solution

Question

Basicallu the question is asking how we can find the concentration of a solution if we know the food coloring. First its red, then its light red(diluted). During the experiment, the light intensity of the red food coloring( no concentration is know), was meausred. Basicallu the question is asking how we can find the concentration of a solution if we know the food coloring. First its red, then its light red(diluted). During the experiment, the light intensity of the red food coloring( no concentration is know), was meausred.

Explanation / Answer

The concentration of food coloring can be deternined using spectrophotometer and taking advantage of Beer Lambert's ;law. The law states that

A=abc

Where A=Absorbance (unitless); a = molar absorptivity (molarity-1cm-1), which is a constant for the absorbing species, b = path length, or thickness of the absorbing layer of a solution (cm), and c = concentration of the solution (molarity).

And if a and b are constant for any given species and path-length, t the absorbance of a solution is directly proportional to the concentration of the absorbing species. Because the absorbance of a solution is easy to measure, this technique is frequently used to measure concentrations of unknown solutions,

For Calculating the concentration of unkwown sample of red fix the wave length between 620 to 780 nm and prepare a calibration chart of known concentration vs absorbance. This allows determination of molar absorbi

viity. Then find out the absorbancec of unknown sample solution anf from the calibration chart ,one can deterimine the concentration.

However, Beer law is not obeyed at high cocnentrations of samples and heence the red colored sample is to be diluted.

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