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Given a glucose standard concentration of 200 mg/dL, with an absorbance of .640. Your patient's serum has an absorbance of .252. Calculate the concentration of glucose in this patient's serum.

User Chris Colla
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1 Answer

28 votes
28 votes

Answer:

concentration of glucose = 78.75 mg/dL

Step-by-step explanation:

The question essentially wants to test the ability to calculate the concentration of a patient's test result done on a spectrophotometer using the absorbance from Beer-Lambert's law, which states that when incident light passes through a medium, the absorbance is directly proportional to the concentration of the medium and inversely to the length of the light path.

Mathematically it is represented as

Absorbance (A) ∝ Concentration (C) (or length of path)

A ∝ C

A = kC

where "k" represents the factors that are kept constant.

As a result we can rewrite the formula as:

A₁ = C₁ - - - - - (1)

A₂ = C₂ - - - - -(2)

And dividing both equations:


image

Next, let us define what is "standard" is; in analytical chemistry, a standard solution is one containing a precisely known concentration of the analyte in question, and it can be applied into the Beer-Lamberts law as follows:


image


image

User Dariober
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