Final answer:
To calculate the molar absorptivity, use the equation A = ɛcl, where A is the absorbance, ɛ is the molar absorptivity, c is the concentration, and l is the path length. Given the absorbance, concentration, and path length, convert the concentration to mol/L and calculate the molar absorptivity. In this case, the molar absorptivity is 4.33 x 10^(10) L mol^(-1) cm^(-1).
Step-by-step explanation:
To calculate the molar absorptivity (extinction coefficient), we can use the Beer-Lambert Law equation: A = ɛcl, where A is the absorbance, ɛ is the molar absorptivity, c is the concentration in mol/L, and l is the path length in cm. Rearranging the equation, we have ɛ = A / (cl). Given that the compound absorbs 65% of the radiation at a concentration of 15 µg/mL and a path length of 1.00 cm, we can convert the concentration to mol/L and calculate the molar absorptivity.
First, we need to convert the concentration from µg/mL to mol/L:
15 µg/mL = 15 x 10^(-6) g/mL = 15 x 10^(-9) g/L = 15 x 10^(-9) x 10^(-3) mol/L = 15 x 10^(-12) mol/L
Next, we can calculate the molar absorptivity using the equation: ɛ = A / (cl) = 0.65 / (15 x 10^(-12) mol/L x 1.00 cm) = 4.33 x 10^(10) L mol^(-1) cm^(-1).