Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 15: Problem 6

Write the formula for the conjugate acid of each of the following bases: (a) \(\mathrm{HS}^{-},(\mathrm{b}) \mathrm{HCO}_{3}^{-}\) (c) \(\mathrm{CO}_{3}^{2-}\) (d) \(\mathrm{H}_{2} \mathrm{PO}_{4}^{-},\) (e) \(\mathrm{HPO}_{4}^{2-}\) (f) \(\mathrm{PO}_{4}^{3-}\) (g) \(\mathrm{HSO}_{4}^{-}\) (h) \(\mathrm{SO}_{4}^{2-},\) (i) \(\mathrm{SO}_{3}^{2-}\)

Short Answer

Expert verified
The conjugate acids for the given bases are: (a) \(\mathrm{H}_{2}\mathrm{S}\), (b) \(\mathrm{H}_{2}\mathrm{CO}_{3}\), (c) \(\mathrm{HCO}_{3}^{-}\), (d) \(\mathrm{H}_{3}\mathrm{PO}_{4}\), (e) \(\mathrm{H}_{2}\mathrm{PO}_{4}^{-}\), (f) \(\mathrm{HPO}_{4}^{2-}\), (g) \(\mathrm{H}_{2}\mathrm{SO}_{4}\), (h) \(\mathrm{HSO}_{4}^{-}\), (i) \(\mathrm{HSO}_{3}^{-}\)

Step by step solution

01

Determine the Conjugate Acids

The process of determining the conjugate acid of a base involves adding a proton (H+) to the base. Let's work this out for each base given:(a) \(\mathrm{HS}^{-}\): Adding a proton to \(\mathrm{HS}^{-}\) results in \(\mathrm{H}_{2}\mathrm{S}\)(b) \(\mathrm{HCO}_{3}^{-}\): Adding a proton to \(\mathrm{HCO}_{3}^{-}\) results in \(\mathrm{H}_{2}\mathrm{CO}_{3}\)(c) \(\mathrm{CO}_{3}^{2-}\): Adding a proton to \(\mathrm{CO}_{3}^{2-}\) results in \(\mathrm{HCO}_{3}^{-}\)(d) \(\mathrm{H}_{2} \mathrm{PO}_{4}^{-}\): Adding a proton to \(\mathrm{H}_{2} \mathrm{PO}_{4}^{-}\) results in \(\mathrm{H}_{3}\mathrm{PO}_{4}\)(e) \(\mathrm{HPO}_{4}^{2-}\): Adding a proton to \(\mathrm{HPO}_{4}^{2-}\) results in \(\mathrm{H}_{2}\mathrm{PO}_{4}^{-}\)(f) \(\mathrm{PO}_{4}^{3-}\): Adding a proton to \(\mathrm{PO}_{4}^{3-}\) results in \(\mathrm{HPO}_{4}^{2-}\)(g) \(\mathrm{HSO}_{4}^{-}\): Adding a proton to \(\mathrm{HSO}_{4}^{-}\) results in \(\mathrm{H}_{2}\mathrm{SO}_{4}\)(h) \(\mathrm{SO}_{4}^{2-}\): Adding a proton to \(\mathrm{SO}_{4}^{2-}\) results in \(\mathrm{HSO}_{4}^{-}\)(i) \(\mathrm{SO}_{3}^{2-}\): Adding a proton to \(\mathrm{SO}_{3}^{2-}\) results in \(\mathrm{HSO}_{3}^{-}\)In every case, notice that the charge of each base is reduced by 1 upon the addition of a proton.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Brønsted-Lowry theory
The Brønsted-Lowry theory is a fundamental concept in chemistry, particularly when it comes to understanding acid-base reactions. According to this theory, an acid is defined as any substance that can donate a proton (H+), and a base is any substance that can accept a proton. This is distinctly different from the original, Arrhenius definition, which restricted acids and bases to substances that produce H+ and OH- ions in water, respectively.

When a Brønsted acid donates a proton, it becomes its conjugate base, while the Brønsted base becomes its conjugate acid after accepting a proton. This is an important concept for visualizing acid-base reactions because it helps explain how substances can act differently under various conditions. For example, water can act as an acid or a base depending on the substance it reacts with; this dual ability is termed amphiprotic nature. In the exercise provided, the goal was to identify the conjugate acid after bases were given a proton, showcasing direct applications of the Brønsted-Lowry theory.
Acid-base reactions
Acid-base reactions are a staple of chemical interactions, where the exchange of protons is the primary event. Recall that according to Brønsted-Lowry, these reactions are essentially proton transfer processes. A typical acid-base reaction involves an acid donating a proton to a base, resulting in the formation of the acid's conjugate base and the base's conjugate acid.

Let's break down the solution provided in the exercise: when we add a proton to a base such as HCO3-, it becomes H2CO3, illustrating the base has accepted a proton and has transformed into its conjugate acid. This two-way street—that substances can be transformed into their conjugates through the gain or loss of a proton—is the dance of acid-base chemistry that keeps our biological and environmental systems in harmony. Understanding these reactions at the molecular level enables chemists and students alike to predict the behavior of substances in various conditions and to calculate the concentrations of acids and bases in solutions, which is vital in many scientific disciplines.
Chemical formulae
Chemical formulae are a way of representing the composition of a chemical substance using the symbols for its constituent elements and numerical subscripts to show the ratio of atoms in the compound. For instance, H2SO4 represents sulfuric acid, with the numeral 2 indicating there are two hydrogen atoms for each sulfur and four oxygen atoms.

In the context of conjugate acids, understanding chemical formulae is key. As seen in the provided solutions, adding a proton to a chemical species invariably changes its chemical formula. It's crucial for students to identify how the addition of an H+ ion to the base's formula reduces the charge by one unit and creates a new substance with distinct properties. For example, adding a proton to SO42- produces HSO4-. Recognizing these patterns in chemical formulae not only helps in memorizing common acids and bases but also aids in mastering the predictive aspect of chemistry where one can infer the outcome of an acid-base reaction based on the initial reactants.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

True or false? If false, explain why each statement is wrong. (a) All Lewis acids are Brønsted acids. (b) The conjugate base of an acid always carries a negative charge. (c) The percent ionization of a base increases with its concentration in solution. (d) A solution of barium fluoride is acidic.

When chlorine reacts with water, the resulting solution is weakly acidic and reacts with AgNO \(_{3}\) to give a white precipitate. Write balanced equations to represent these reactions. Explain why manufacturers of household bleaches add bases such as \(\mathrm{NaOH}\) to their products to increase their effectiveness.

Compare the \(\mathrm{pH}\) of a \(0.040 \mathrm{M} \mathrm{HCl}\) solution with that of a \(0.040 \mathrm{M} \mathrm{H}_{2} \mathrm{SO}_{4}\) solution. (Hint: \(\mathrm{H}_{2} \mathrm{SO}_{4}\) is a strong acid; \(K_{\mathrm{a}}\) for \(\left.\mathrm{HSO}_{4}^{-}=1.3 \times 10^{-2} .\right)\)

Which of the following is the stronger base: \(\mathrm{NF}_{3}\) or \(\mathrm{NH}_{3} ?\) (Hint: \(\mathrm{F}\) is more electronegative than \(\left.\mathrm{H} .\right)\)

The ion product of \(\mathrm{D}_{2} \mathrm{O}\) is \(1.35 \times 10^{-15}\) at \(25^{\circ} \mathrm{C}\). (a) Calculate \(\mathrm{pD}\) where \(\mathrm{pD}=-\log \left[\mathrm{D}^{+}\right]\). (b) For what values of \(\mathrm{pD}\) will a solution be acidic in \(\mathrm{D}_{2} \mathrm{O} ?\) (c) Derive a relation between \(\mathrm{pD}\) and \(\mathrm{pOD}\).
See all solutions

Recommended explanations on Chemistry Textbooks

Kinetics

Read Explanation

The Earths Atmosphere

Read Explanation

Organic Chemistry

Read Explanation

Chemical Reactions

Read Explanation

Chemistry Branches

Read Explanation

Making Measurements

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free