0.5g of Solid A is dissolved in 1L solvent to give a concentration of concentration 0.5g/L.

UV absorbance spectrum was collected.
How to calculate the absorptivity on the dried basis?

To calculate the absorptivity on the dried basis, you need to determine the concentration of the solid in the solution after it has been dried. Here's how you can do it:

1. Start by calculating the mass of the solid A that was dissolved in the solution. You are given that 0.5g of Solid A was dissolved in 1L of solvent, resulting in a concentration of 0.5g/L. This means that the mass of Solid A in the solution is 0.5g.

2. Now, you need to determine the concentration of Solid A on the dried basis. To do this, you need to evaporate the solvent from the solution and weigh the remaining solid. Let's assume that after evaporation, you obtained 0.3g of Solid A.

3. Calculate the concentration of Solid A on the dried basis. This can be done by dividing the mass of Solid A after drying by the volume of the solution before drying. In this case, the concentration on the dried basis is 0.3g/1L = 0.3g/L.

4. The absorptivity (ε) on the dried basis can now be calculated using the Beer-Lambert Law. The Beer-Lambert Law relates the absorbance (A) of a substance to its concentration (c) and the path length of the sample (l) using the equation A = εcl.

Since you know the concentration on the dried basis (0.3g/L) and the path length of the sample (typically provided in cm), you can rearrange the equation to solve for the absorptivity (ε) as follows:

ε = A / (cl)

Note that you mentioned that an UV absorbance spectrum was collected. From the spectrum, you can determine the absorbance at a specific wavelength (A). Once you have that value, plug it into the equation along with the concentration on the dried basis (0.3g/L) and the path length (e.g., 1 cm) to calculate the absorptivity (ε) on the dried basis.

Overall, the absorptivity on the dried basis can be calculated using the Beer-Lambert Law and the concentration on the dried basis, absorbance value, and path length.