## Step 1: Drawing Chromatogram (A) **Requirement:** - Two analytes: **Analyte I** and **Analyte II** - **Selectivity (α):** 2.5 - **Resolution:** ~.8 (low resolution, partial overlap) **Explanation:** Selectivity (α) of 2.5 means the two peaks should have different retention times, but a resolution of .8 means the peaks will significantly overlap. The peaks are not completely separated. **Sketch (A):** ``` | /\ | / \ | /\ / \ | / \ / \ |----/----\--/--------\---- t1 t2 ``` - **Peak 1 (Analyte I):** at t1 - **Peak 2 (Analyte II):** at t2 (t2 > t1, but peaks overlap) ### Explanation (A): - The two peaks are not baseline separated; there is considerable overlap. - This indicates a resolution less than 1 (here, .8). - The difference in retention times reflects the selectivity of 2.5. --- ## Step 2: Drawing Chromatogram (B) **Requirement:** - Two analytes: **Analyte I** and **Analyte II** - **Selectivity (α):** 2.5 - **Resolution:** 1.5 (good separation) **Explanation:** Both selectivity and resolution are high. The peaks should be well separated, with little/no overlap. **Sketch (B):** ``` | /\ | / \ |----/----\ /\ | \ / \ | \/ \--- t1 t2 ``` - **Peak 1 (Analyte I):** at t1 - **Peak 2 (Analyte II):** at t2 (t2 > t1, peaks do not overlap) ### Explanation (B): - The two peaks are clearly separated, indicating a resolution of 1.5. - The difference in retention times still reflects a selectivity of 2.5. --- ## **Final Answer** - **(A):** Peaks overlap significantly (Resolution = .8), both analytes are not baseline separated. - **(B):** Peaks are baseline separated (Resolution = 1.5), both analytes are clearly resolved. Both chromatograms have a selectivity (α) of 2.5, but differ in how well the peaks are separated.