Question

A calibration curve constructed from absorbance values of solutions containing a known concentration of permanganate ions has the following best-fit line:

y = (3.62× 10^3 L/mol) x
where y is the absorbance of the solution at 525 nm and x is the concentration of MnO4- (aq) in mol/L. The path length of the cuvettes used in the experiment is 1 cm. Based on this information, what is the molar absorptivity of MnO4- (aq) at 525 nm?

Answer 1

3.62×10³ L/mol

Step-by-step explanation:

Beer-Lambert law relates the absorbance of a sample and its concentration. Its formula is:

A = ε×C×l

Where A is absorbance of the sample, ε is molar absorptivity (A constant f each sample), C its concentration and l is path length

Now, the formula obtained was:

y = (3.62×10³ L/mol) x

Where Y ia absorbance = A, x its concentration = C and 1cm is path length.

You can write:

A = (3.62×10³ L/mol)×C×l

That means, molar absorptivity of your sample under the meaured conditions is:

3.62×10³ L/mol