3 a student separated an unknown mixture of ions

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3. A student separated an unknown mixture of ions using the procedure of Part A. When the spots were made visible, a faint spot corresponding to Cu 2+ was seen. However, the student later learned that the unknown did not contain Cu 2+ , Which of the following could cause this result? a. The same spotting capillary was used to spot the Cu 2+ sample and the unknown sample. b.The Cu 2+ sample was contaminated with Co 2+ and Fe 3+ c. The chromatography paper was not trimmed to the correct dimensions. d.The position of the mobil-phase front was incorrectly marked. Explain your answer. The same spotting capillary was to spot the cu2+ of the unknown sample. There was cross-contamination of two different substances will cause them to leave trace mount of the Ion's contained in both, not the one tested.
4. A student performs the HCl tests on the three solid samples as described in Step 5 of Part B and gets the same result for the solid CaCO 3 sample and the mixture. Which of the following statements is true concerning these results?
Score 0.00 of 1 Instructor Comments a 5. In Part C, chemical tests were used to differentiate between the two substances in the mixture. Which of the following physical properties could also have been used conveniently?
Explain your answer.
6. A student performs Part C, but instead of discarding the filtrate, the student heats it carefully and eventually ends up with a small amount of solid in the beaker. What is the solid? 3 4 Explain your answer.

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