1. a. Dye have very high molar absorptivity. Why is this an advantage for their use...

1. a. Dye have very high molar absorptivity. Why is this an advantage for their use in food products?

b. How do we "blank the spectrophotometer"? Why is it done?

Expert Solution

(a)Fromthe LambertbeerLaw we know that where A=amount of light absorbed, $\varepsilon$ =molar absorptivity, C=concentration, if a compound has molar absorptivity has high absorbance, so by using a small quantity of dye which will efficienlty absorb sufficient amount of light we will be able to visualize deep colour for longer time.

(b) generally we are doing 'blank the spectrophotometer' by meassuirng the absorbance value of the cuvette and the solution in which the sample is dissolved or mixed and set the absorbance value to zero of the spectrophotometer before doing any meassuremnet.

It is done to remove the error in the meassurement. because all the material has some absorbance value. when we are dissoving our experimental sample in the suitable medium (water, ethanol DMSO or any other solvent) and keep it in some cuvette, at that time the spectrophotometer will meassure the absorbance value for the sample+medium(solvent)+cuvette,but our main aim is to determine the absorbance value of our sample only ,so we should subtract the absorbance value for medium(solvent)+cuvette to get proper data of our sample. this work is done by meassuring blank in the spectrophotometer.

queen_honey_blossom answered 3 years ago

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