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Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?
  • a)
    N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s rule
  • b)
    N1 is protonated because it is sp3 hybridized
  • c)
    N3 is protonated because it is sp2 hybridized
  • d)
    N1 is protonated because the lone pair is part of the aromatic pi system
Correct answer is option 'C'. Can you explain this answer?
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Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is...
The lone pair on N1 is involved in aromaticity and will be least likely to act as a base as harsh conditions are required for the loss of aromatic character. In mild conditions such as near pH 7, N3 would be protonated for two reasons:
i) The lone pair on N3 is perpendicular to the delocalised pi-electron system and hence is not in resonance with the six pi electrons. This is because the lone pair lies in a vacant p-orbital (unhybridised).
ii) The basicity is greater due to a greater s-character (sp2) leading to more negative charge on N3 as compared to N1, which is sp3 hybridised.
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Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is...
If we take a view upon hybridization,then N¹ is sp3 hybridised and N³ is sp2 hybridised,we know more will be the S character more will be it's electronegativity so that less will be it's Basicity and less will be it's pronataed character .so that N3 will be easily protonated
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Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer?
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Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer? for Chemistry 2024 is part of Chemistry preparation. The Question and answers have been prepared according to the Chemistry exam syllabus. Information about Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for Chemistry 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer?.
Solutions for Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for Chemistry. Download more important topics, notes, lectures and mock test series for Chemistry Exam by signing up for free.
Here you can find the meaning of Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer?, a detailed solution for Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer? has been provided alongside types of Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Imidazole has a pKa = 7 with respect to its conjugate acid. Which N is protonated in this conjugate acid and why?a)N1 because imidazole is an aromatic heterocycle where n = 1 as per Huckel’s ruleb)N1 is protonated because it is sp3 hybridizedc)N3 is protonated because it is sp2 hybridizedd)N1 is protonated because the lone pair is part of the aromatic pi systemCorrect answer is option 'C'. Can you explain this answer? tests, examples and also practice Chemistry tests.
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