Ap Stat Review
Sample Exercise 16.1 Identifying Conjugate Acids and Bases
(a) What is the conjugate base of each of the following acids: HClO4, H2S, PH4+, HCO3–? (b) What is the conjugate acid of each of the following bases: CN–, SO42–, H2O, HCO3– ? Solution Analyze: We are asked to give the conjugate base for each of a series of species and to give the conjugate acid for each of another series of species. Plan: The conjugate base of a substance is simply the parent substance minus one proton, and the conjugate acid of a substance is the parent substance plus one proton. Solve: (a) HClO4 less one proton (H+) is ClO4–. The other conjugate bases are HS–, PH3, and CO32–. (b) CN– plus one proton (H+) is HCN. The other conjugate acids are HSO4–, H3O+, and H2CO3. Notice that the hydrogen carbonate ion (HCO3–) is amphiprotic. It can act as either an acid or a Practice Exercise base. Write the formula for the conjugate acid of each of the following: HSO3–, F– , PO43–, CO. Answers: H2SO3, HF, HPO42–, HCO+
Chemistry: The Central Science, Eleventh Edition By Theodore E. Brown, H. Eugene LeMay, Bruce E. Bursten, and Catherine J. Murphy With contributions from Patrick Woodward
Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved.
Sample Exercise 16.2 Writing Equations for Proton-Transfer Reactions
The hydrogen sulfite ion (HSO3–) is amphiprotic. (a) Write an equation for the reaction of HSO3– with water, in which the ion acts as an acid. (b) Write an equation for the reaction of HSO3– with water, in which the ion acts as a base. In both cases identify the conjugate acid–base pairs. Solution Analyze and Plan: We are asked to write two equations representing reactions between HSO3– and water, one in which HSO3– should donate a proton to water, thereby acting as a Brønsted– Lowry acid, and one in which HSO3– should accept a proton from water, thereby acting as a base. We are also asked to identify the conjugate pairs in each equation.
(a) What is the conjugate base of each of the following acids: HClO4, H2S, PH4+, HCO3–? (b) What is the conjugate acid of each of the following bases: CN–, SO42–, H2O, HCO3– ? Solution Analyze: We are asked to give the conjugate base for each of a series of species and to give the conjugate acid for each of another series of species. Plan: The conjugate base of a substance is simply the parent substance minus one proton, and the conjugate acid of a substance is the parent substance plus one proton. Solve: (a) HClO4 less one proton (H+) is ClO4–. The other conjugate bases are HS–, PH3, and CO32–. (b) CN– plus one proton (H+) is HCN. The other conjugate acids are HSO4–, H3O+, and H2CO3. Notice that the hydrogen carbonate ion (HCO3–) is amphiprotic. It can act as either an acid or a Practice Exercise base. Write the formula for the conjugate acid of each of the following: HSO3–, F– , PO43–, CO. Answers: H2SO3, HF, HPO42–, HCO+
Chemistry: The Central Science, Eleventh Edition By Theodore E. Brown, H. Eugene LeMay, Bruce E. Bursten, and Catherine J. Murphy With contributions from Patrick Woodward
Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved.
Sample Exercise 16.2 Writing Equations for Proton-Transfer Reactions
The hydrogen sulfite ion (HSO3–) is amphiprotic. (a) Write an equation for the reaction of HSO3– with water, in which the ion acts as an acid. (b) Write an equation for the reaction of HSO3– with water, in which the ion acts as a base. In both cases identify the conjugate acid–base pairs. Solution Analyze and Plan: We are asked to write two equations representing reactions between HSO3– and water, one in which HSO3– should donate a proton to water, thereby acting as a Brønsted– Lowry acid, and one in which HSO3– should accept a proton from water, thereby acting as a base. We are also asked to identify the conjugate pairs in each equation.