(Solved): 4. Two species, A and B, elute from a chromatographic column with retention times of: tRAA=8.136 ...

4. Two species, A and B, elute from a chromatographic column with retention times of: $t_{RAA}=8.136\min t_{RBB}=8.387\min t_M=0.509\min$ The dead time for the column under the measurement parameters used is ${\mathrm{t}}_{\mathrm{M}}=0.509\min$. Determine the average number of theoretical plates required to achieve a resolution between compounds $\mathrm{A}$ and $\mathrm{B}$ of $\mathrm{R}=0.950$. 5. An unknown sample containing lead $(\mathrm{Pb})$ is analyzed using flame atomic absorption spectrometry. The following absorbance measurements were recorded for two standard solutions and the unknown sample. Determine the concentration of $\mathrm{Pb}$ in the unknown sample.