2 a student collects chromatographic data as you did

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2. A student collects chromatographic data as you did in part A and calculates the RF value of 1.4 for one of the solute spots. Which of the following is true a) The calculated RF value might be correct b) The calculated RF value is probably incorrect c ) The calculated value RF value is definitely incorrect Explain your answer The Rf value should always be less than 1as more than 1 means the spot moved faster than the solvent which is unreliable.
3. A student separated the 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 Cu2+. Which of the following could cause the result
Explain your answer probably a capillary used to spot the unknown sample had previously been used with Cu 2+ therefore it was contaminated
4. A student performs a 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 mixture. Which of the following is true concerning the result
Explain your answers 5. In part C, chemical tests were used to differentiate between the two substances in the mixture. Which one of the following physical properties could also have been used conveniently?
6. A student performs part C but instead of discarding the filtrate the student heats it carefully, evaporates the liquid and eventually ends up with a small amount of solid in a beaker. What was the solid? a) Caco3 b) cuso4 c) a mixture of caco3 and cuso4
Explain your answer

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