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\$A={\\rm log(\\frac{{\\it{I}}_0}{{\\it {I}}_t})}=\\varepsilon ~c~l\$

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Where

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\$I_t=\\var{it}\\% \$

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\$~\$

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Substitute into \$A={\\rm log(\\frac{{\\it I}_o}{{\\it I}_t})}=\\varepsilon~c~l\$

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\$I_{\\rm 0} ~\\rm is~ \\therefore ~100~\\% ~relative ~to~ the~ observed ~ray\$

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\$A={\\rm log(\\frac{\\var{io}}{\\var{it}})}=\\var{a}\\ \$

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Remember to convert the value of pathlength from mm to cm

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\$\\var{l}~\\rm mm=\\var{l_cm}~cm\$

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Rearrange for $\\epsilon$

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\$\\epsilon=\\frac{A}{c~ \\times~ l}=\\frac{\\var{A}}{\\var{conc}~\\rm mol~ dm^{-3}~\\times \\var{l_cm}~cm}=\\var{epsilon}~\\rm mol^{-1} ~dm^{3}~cm^{-1}\$

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$A={\\rm log(\\frac{{\\it {I}}_0}{{\\it {I}}_t})}=\\varepsilon ~c~l$

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When light passes through a {l} mm cell containing a concentration, c, of solute of {conc_coeff} $\\times$ 10{conc_log} mol dm-3, the transmitted light intensity, It, is {it} % of I0. Calculate the molar absorption coefficient, $\\epsilon$, of the solute at the wavelength at which the experiment is performed in units of mol-1 dm3 cm-1.

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What is the value of epsilon, $\\epsilon$, in units of mol-1 dm3 cm-1?

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