Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 14: Problem 82

Rank the following species in order of decreasing acid strength: \(\mathrm{H}_{2} \mathrm{SO}_{4}, \mathrm{H}_{2} \mathrm{SO}_{3}, \mathrm{HSO}_{3}^{-}\)

Short Answer

Expert verified
\( \mathrm{H}_{2} \mathrm{SO}_{4} > \mathrm{H}_{2} \mathrm{SO}_{3} > \mathrm{HSO}_{3}^{-} \).

Step by step solution

01

Identify Acid Strength Factors

Consider the number of oxygen atoms and the oxidation state of sulfur in each species. More oxygen atoms typically increase acid strength due to the inductive effect and stabilization of the conjugate base.
02

Analyze \( \mathrm{H}_{2} \mathrm{SO}_{4} \)

\( \mathrm{H}_{2} \mathrm{SO}_{4} \) has four oxygen atoms and sulfur is in the +6 oxidation state. It is a strong acid because the high number of oxygen atoms stabilizes the conjugate base \( \mathrm{HSO}_{4}^{-} \).
03

Analyze \( \mathrm{H}_{2} \mathrm{SO}_{3} \)

\( \mathrm{H}_{2} \mathrm{SO}_{3} \) has three oxygen atoms and sulfur is in the +4 oxidation state. It is weaker than \( \mathrm{H}_{2} \mathrm{SO}_{4} \) because it has fewer oxygen atoms.
04

Analyze \( \mathrm{HSO}_{3}^{-} \)

\( \mathrm{HSO}_{3}^{-} \) is the conjugate base of \( \mathrm{H}_{2} \mathrm{SO}_{3} \). As a conjugate base of a weak acid, it is even weaker in terms of acid strength compared to \( \mathrm{H}_{2} \mathrm{SO}_{3} \).
05

Rank the Species

Based on the analysis, rank the species in order of decreasing acid strength: \( \mathrm{H}_{2} \mathrm{SO}_{4} \), \( \mathrm{H}_{2} \mathrm{SO}_{3} \), \( \mathrm{HSO}_{3}^{-} \).

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.

Acid Strength Factors
Understanding what makes an acid strong or weak is crucial for ranking acids correctly. Several factors influence acid strength:
  • Number of Oxygen Atoms: More oxygen atoms typically increase acid strength. Oxygen's high electronegativity pulls electron density away, enhancing the polarity of the O-H bond and making it easier to donate a proton (H+).
  • Oxidation State: A higher oxidation state on the central atom (like sulfur in our example) increases acid strength. This is because higher oxidation states mean the central atom pulls electron density more effectively, weakening the O-H bond.
  • Inductive Effect: Electronegative atoms like oxygen create an inductive effect. This effect stabilizes the conjugate base by distributing the negative charge more effectively.
By considering these factors, you can systematically determine acid strength and properly rank different species.
Conjugate Base Stability
The stability of a conjugate base is directly linked to the acid's strength. Strong acids have very stable conjugate bases, while weak acids have less stable conjugate bases.
  • Resonance Stabilization: If a conjugate base can delocalize its negative charge over several atoms through resonance, it becomes more stable.
  • Electronegative Atoms: Having electronegative atoms like oxygen in the conjugate base can increase stability. These atoms pull electron density away from the charged site, spreading out the negative charge.
For example, in sulfuric acid (\textbf{H}\(_2\textbf{SO}_4\)), the conjugate base (\textbf{HSO}_4\(^-$$) is highly stabilized due to resonance and the presence of multiple oxygen atoms. This stabilization makes \)\textbf{H}\(_2\textbf{SO}_4\)) a strong acid. In contrast, \(\textbf{HSO}_3\)^-$$, the conjugate base of sulfurous acid (\(\textbf{H}_2\textbf{SO}_3\))), is less stabilized, making $$\textbf{H}\(_2\textbf{SO}_3\)) a weaker acid.
Oxidation State
The oxidation state of the central atom in an acid influences its strength.
  • Definition: The oxidation state is the charge of the central atom if all bonds were considered 100% ionic.
  • Impact on Acid Strength: A higher oxidation state increases the electron-withdrawing power of the central atom. This, in turn, weakens the O-H bond, making it easier to donate a proton (H+).
    For example:

    • Sulfuric Acid (\textbf{H}\(_2\textbf{SO}_4\))): In \(\textbf{H}_2\textbf{SO}_4\))), sulfur is in the +6 oxidation state. This high oxidation state significantly increases the acid strength.
    • Sulfurous Acid (\(\textbf{H}_2\textbf{SO}_3\))): In $$\textbf{H}$$_2\textbf{SO}_3\(), sulfur is in the +4 oxidation state. Although still moderately strong, it is weaker than \)\textbf{H}\()\)_2\textbf{SO}_4\() due to the lower oxidation state.
    • Conjugate Base (\)\textbf{HSO}\(_3\)^-$$): The conjugate base of \({H}$$_2\textbf{SO}_3\)), has sulfur in a +4 oxidation state. As the conjugate base of a weaker acid, it is even weaker in acid strength.
    Understanding the oxidation state helps you predict and explain the acid strength of different species.

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

A common method for producing a gaseous hydride is to treat a salt containing the anion of the volatile hydride with a strong acid. (a) Write an equation for each of the following examples: ( 1 ) the production of HF from \(\mathrm{CaF}_{2} ;\) (2) the production of \(\mathrm{HCl}\) from \(\mathrm{NaCl} ;\) (3) the production of \(\mathrm{H}_{2} \mathrm{~S}\) from FeS. (b) In some cases, even as weak an acid as water can be used for this preparation if the anion of the salt has a sufficiently strong attraction for protons. An example is the production of \(\mathrm{PH}_{3}\) from \(\mathrm{Ca}_{3} \mathrm{P}_{2}\) and water. Write the equation for this reaction. (c) By analogy, predict the products and write the equation for the reaction of \(\mathrm{Al}_{4} \mathrm{C}_{3}\) with water.

How do atomic properties account for the low densities of the Group \(1 \mathrm{~A}(1)\) elements?

Semiconductors made from elements in Groups \(3 \mathrm{~A}(13)\) and \(5 \mathrm{~A}(15)\) are typically prepared by direct reaction of the elements at high temperature. An engineer treats \(32.5 \mathrm{~g}\) of molten gallium with \(20.4 \mathrm{~L}\) of white phosphorus vapor at \(515 \mathrm{~K}\) and \(195 \mathrm{kPa}\). If purification losses are \(7.2 \%\) by mass, how many grams of gallium phosphide will be prepared?

Compounds such as \(\mathrm{NaBH}_{4}, \mathrm{Al}\left(\mathrm{BH}_{4}\right)_{3},\) and \(\mathrm{LiAlH}_{4}\) are com- plex hydrides used as reducing agents in many syntheses. (a) Give the oxidation state of each element in these compounds. (b) Write a Lewis structure for the polyatomic anion in \(\mathrm{NaBH}_{4}\), and predict its shape.

Unlike other Group \(2 \mathrm{~A}(2)\) metals, beryllium reacts like aluminum and zinc with concentrated aqueous base to release hydrogen gas and form oxoanions of formula \(\mathrm{M}(\mathrm{OH})_{4}^{n-}\). Write equations for the reactions of these three metals with \(\mathrm{NaOH}\).
See all solutions

Recommended explanations on Chemistry Textbooks

Chemistry Branches

Read Explanation

Ionic and Molecular Compounds

Read Explanation

Chemical Analysis

Read Explanation

Physical Chemistry

Read Explanation

Chemical Reactions

Read Explanation

Organic Chemistry

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