Chromatography worksheet - Free Printable

- First, look closely: The image contains two separate chromatography problems. For question 3, I need to compare the ink sample's spots with those of dyes 1, 2, 3, and 4 to identify which dyes are present in the ink. For question 4, I need to compare the spots from the tinned food samples (apricots, beans, corn, tomatoes) with the reference spots for artificial additives P, Q, and R to determine which food has no additives.

- Next, find information: I will analyze the chromatograms for each question by comparing the positions of the spots.

- Then, review the findings:

For question 3:
- The "ink" lane has three distinct spots at different heights.
- Comparing these to the dye lanes:
- Dye 1 has a spot that matches the top spot in the ink.
- Dye 2 has a spot that matches the middle spot in the ink.
- Dye 3 has a spot that does not match any spot in the ink.
- Dye 4 has a spot that matches the bottom spot in the ink.
- Therefore, the ink contains dyes 1, 2, and 4. However, since the options only allow for two dyes, I must choose the pair that best fits. Option B (1 and 4) is incorrect because it misses dye 2. Option A (1 and 2) is also incorrect as it misses dye 4. Option C (2 and 3) is wrong because dye 3 is not in the ink. Option D (2 and 4) is the closest, but it still misses dye 1. Given the constraints, I need to re-evaluate. Actually, looking again, the ink has spots that align perfectly with dyes 1, 2, and 4. Since no option includes all three, I must have misread. Let me check the options again. The correct answer should be based on the exact matches. Dye 1 and dye 4 spots match two of the ink's spots, and dye 2 matches another. But since the question asks "which dyes does the ink contain?" and the options are pairs, perhaps there's an error. Wait, let me count the spots again. The ink has three spots. Dye 1 has one spot matching the top ink spot. Dye 2 has one spot matching the middle ink spot. Dye 4 has one spot matching the bottom ink spot. So the ink contains dyes 1, 2, and 4. But since the options don't include this, I need to see if any option is correct. Option B is 1 and 4, which covers two spots, but misses 2. This is confusing. Perhaps I should consider that the question might expect the combination that matches the most spots. But logically, the ink contains all three. However, given the multiple-choice format, I must select the best available answer. Let me assume that the question intends for us to pick the pair that matches two of the three spots. But that doesn't make sense. Alternatively, maybe I miscounted. Let me zoom in on the ink and dye lanes to confirm the spot positions.