A-LevelChemistryOrganic synthesisFeb/Mar 2021Paper 1 Q271 Mark
In this question you can assume that ¹H and ³H have the same chemical properties. A sample of ethanal contains only one isotope of hydrogen, ¹H. It is reduced to compound Z, C₂H₆O, in a nucleophilic addition reaction using NaBH₄. All the hydrogen atoms in the NaBH₄ are the ³H isotope. NaBH₄ CH₃CHO → C₂H₆O compound Z Compound Z is then oxidised back to ethanal and water. C₂H₆O + [O] → CH₃CHO + H₂O Which statement about the final mixture of products is correct?
ABoth ethanal and water contain ³H atoms.
BEthanal is the only product containing ³H atoms.
CNeither ethanal nor water contain ³H atoms.
DWater is the only product containing ³H atoms.
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The correct answer is A. This question tests the candidate's understanding of organic synthesis within the Chemistrysyllabus. The examiner's mark scheme requires...
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