The table shows the base ionisation constant, Kb, for several selected compounds.(a)CompoundC6H5NH2Kb3.8x10-101.7x10-6N2H4NH31.8x10-5NH2OH1.1x10-8i.Arrange the compounds in order of increasing strength of base.ii.Give the structure of conjugate acid for each compound and arrange themin order of increasing strength of acid.(b) The percentage ionisation of 0.010 M NH3 solution was 4.2 % ionisation.Calculate Kb.1.8x105

Higher the value of Kb , higher will be the strength of base. Stronger base will have weak conjugate…

The table shows the base ionisation constant, Kb, for several selected compounds. (a) Compound C6H5NH2 Кь 3.8x10-10 1.7×10-6 N2H4 NH3 1.8×10-5 NH2OH 1.1x10-8 i. Arrange the compounds in order of increasing strength of base. Give the structure of conjugate acid for each compound and arrange them in order of increasing strength of acid. ii. (b) The percentage ionisation of 0.010 M NH3 solution was 4.2 % ionisation. Calculate Kb. 1.8x105

The table shows the base ionisation constant, Kb, for several selected compounds. (a) Compound C6H5NH2 Кь 3.8x10-10 1.7×10-6 N2H4 NH3 1.8×10-5 NH2OH 1.1x10-8 i. Arrange the compounds in order of increasing strength of base. Give the structure of conjugate acid for each compound and arrange them in order of increasing strength of acid. ii. (b) The percentage ionisation of 0.010 M NH3 solution was 4.2 % ionisation. Calculate Kb. 1.8x105

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter4: Acids And Bases

Section: Chapter Questions

Problem 4.10P: Complete a net ionic equation for each proton-transfer reaction using curved arrows to show the flow...

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16-27 Guanidine, p/Ca 13.6, is a very strong base, almost as basic as hydroxide ion. NH NH2+ II II H2N—C—NH2 + H2O H2N—C—NH2 + OH" Guanidine Guanidinium ion pKb = 13.6 Complete the Lewis structure for guanidine, showing all valence electrons. The remarkable basicity of guanidine is attributed to the fact that the positive charge on the guanidinium ion is delocalized by resonance over the three nitrogen atoms. This delocalization increases the stability of the guanidinium ion relative to the ammonium ion or substituted ammonium ions. Draw three equivalent contributing structures for the guanidinium ion and show by the use of curved arrows how these three contributors are related. Propose an explanation for the fact that protonation occurs on the C=NH nitrogen rather than on one of the —NH., nitrogens. (Hint: Consider the resonance stabilization of the structure formed by protonation on a —NH., nitrogen compared with the resonance stabilization of the structure formed by protonation on the =NH nitrogen.) Predict the N—C—N bond angles in the hybrid. Which is the stronger acid, the ammonium ion or the guanidinium ion?