Chemistry, 05.08.2020 17:01 djennings8055
You have to separate a solid mixture of two compounds (benzophenone and biphenyl) using column chromatography. You perform a preliminary TLC and you determine that a mixture of ethyl acetate: hexane = 50:50 is the best solvent.
1. Which one of the two compounds you expect to be eluted first? Explain your answer.
2. You prepare the column, put the sample at the top of the column and pass through a mixture of ethyl acetate: hexanes = 50:50 and collect fractions as they are dripping at the bottom of the column. Analysis of the collected portion through TLC shows that the compounds did not get separated and the solvent mixture suggested by the preliminary TLC did not work as expected. Propose a possible cause.
3. In an effort to attempt to correct the outcome from question 2 you will use only hexanes as the solvent. Analysis of the collected fraction shows the presence of only one compound. Which one do you think it is, benzophenone or biphenyl? Where is the other compound? Explain your answer.
4. In an effort to attempt to correct the outcome from question 2 you will use only ethyl acetate as the solvent. Analysis of the collected fraction shows the presence of only one compound. What outcome do you predict? Which one do you think it is, benzophenone or biphenyl? Explain your answer.
5. What would be in your opinion the best way to use the two solvents to ensure a good separation? Explain your answer. Be specific about order of addition to the column, concentration, etc.
Answers: 3
Chemistry, 22.06.2019 04:30, akeemedwards12
Both josef loschmidt and amedeo avogadro contributed to our understanding of basic molecular numbers, sizes, and reaction ratios. neither scientist discovered “avogadro’s number” in the form we use it today (6.02 x 10 23). still, there’s a controversy over the name. research the contributions from these two scientists and read about how avogadro’s number got its name. briefly state what you think this number should be called, providing key details of each scientist’s contributions to this concept and a solid rationale for your case in naming the number.
Answers: 2
You have to separate a solid mixture of two compounds (benzophenone and biphenyl) using column chrom...
Mathematics, 26.06.2019 11:20
English, 26.06.2019 11:20
Chemistry, 26.06.2019 11:30
Mathematics, 26.06.2019 11:30