A 3.42 × 10−⁵ M solution of dibenzalacetone in ethanol produced an absorbance of 0.753 in a 1.00 cm cell. Based on this data, what is ε for this compound?

Question

Quizplus · Accepted Answer

The molar absorptivity (ε) can be calculated using Beer-Lambert Law: A = εlc, where A is absorbance, l is the path length of the cell (in cm), c is the concentration of the solution (in M), and ε is the molar absorptivity. Given A = 0.753, l = 1.00 cm, and c = 3.42 × 10^-5 M, rearranging the formula to solve for ε gives ε = A / (lc) = 0.753 / (1.00 * 3.42 × 10^-5) = 2.20 × 10^4 M^-1cm^-1.

A 342 × 10−5 M Solution of Dibenzalacetone in Ethanol Produced

A 342 × 10−⁵ M Solution of Dibenzalacetone in Ethanol Produced