Answer:
The molar absorptivity coefficient is, [tex]16.67 M^{-1}cm^{-1}[/tex].
Explanation:
Using Beer-Lambert's law :
Formula used :
[tex]A=\epsilon \times C\times l[/tex]
[tex]A=\log \frac{I_o}{I}[/tex]
[tex]\log \frac{I_o}{I}=\epsilon \times C\times l[/tex]
where,
A = absorbance of solution
C = concentration of solution = [tex]0.03 mol/L=0.03 M[/tex]
l = path length = 2 cm
[tex]I_o[/tex] = incident light
[tex]I[/tex] = transmitted light
[tex]\epsilon[/tex] = molar absorptivity coefficient = ?
A compound absorb 90 % of the light and transmit 10% of light.
Transmittance = 10% = 0.1
[tex]0.1=\frac{I}{I_o}[/tex]
[tex]A=\log \frac{I_o}{I}=\log \frac{1}{0.1}=1[/tex]
Now put all the given values in the above formula, we get the molar absorptivity coefficient.
[tex]1=\epsilon \times (0.03 M)\times ( 2 cm)[/tex]
[tex]\epsilon=16.67 M^{-1}cm^{-1}[/tex]
Therefore, the molar absorptivity coefficient is, [tex]16.67 M^{-1}cm^{-1}[/tex].
