Question

A 3-column table with 2 rows titled Table 2 Diffusion Tests. Column 1 has entries Color of Solution in Dialysis Tube, Color of Solution in Beaker. Column 2 is labeled Step 4: Test for Diffusion Starch with entries Clear initial color and Black after 15 minutes, Yellow initial color and Yellow after 15 minutes. Column 3 is labeled step 7: Test for Diffusion of Glucose with entries Not observed, Light Blue initial color and Red after 15 minutes.
Analysis:
diffused though the semipermeable membrane.

Answer 1

Table 2 — Diffusion Tests

Location | Step 4: Test for Diffusion (starch) | Step 7: Test for Diffusion (glucose)
---|---|---
Color of solution in dialysis tube | Clear (initial) → Black (after 15 min) | Not observed
Color of solution in beaker | Yellow (initial) → Yellow (after 15 min) | Light blue (initial) → Red (after 15 min)

Analysis:
Iodine diffused through the semipermeable membrane into the dialysis tube (turning the starch-containing solution black), but starch did not diffuse out into the beaker. Glucose diffused out of the dialysis tube into the beaker (Benedict’s reagent in the beaker changed from light blue to red).