Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 16: Problem 124

Identify the Lewis acid and Lewis base among the reactants in each equation. a. Ag+(aq) + 2 NH3(aq)Ag(NH3)2+(aq) b. AlBr3 + NH3H3NAlBr3 c. F-(aq) + BF3(aq)BF4-(aq)

Short Answer

Expert verified
a. Lewis acid: Ag+, Lewis base: NH3; b. Lewis acid: AlBr3, Lewis base: NH3; c. Lewis acid: BF3, Lewis base: F-.

Step by step solution

01

Identify Lewis Acid and Lewis Base in Reaction a

A Lewis acid is an electron pair acceptor, while a Lewis base is an electron pair donor. Here, Ag+ is the Lewis acid because it accepts a pair of electrons from each of the NH3 molecules (which are the Lewis bases), as they donate a pair of electrons to form the complex, Ag(NH3)2+.
02

Identify Lewis Acid and Lewis Base in Reaction b

In the second reaction, AlBr3 is the Lewis acid because it can accept a pair of electrons. NH3 is the Lewis base because it donates its lone pair of electrons to AlBr3 to form the H3NAlBr3 complex.
03

Identify Lewis Acid and Lewis Base in Reaction c

For the third reaction, BF3 is a Lewis acid as it is an electron pair acceptor due to the boron atom being electron deficient. The F- ion is the Lewis base in this reaction because it donates a pair of electrons to BF3 to form BF4-.

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.

Lewis Acid
A Lewis acid is best described as a substance that can accept an electron pair. In chemical reactions, Lewis acids accept electron pairs from Lewis bases to form coordination complexes.

For example, take silver ion, Ag+, from the provided exercise. It is a Lewis acid because it has a positive charge, indicating a deficiency of electrons. Hence, it accepts an electron pair from ammonia (NH3), a Lewis base, resulting in a new complex. This electron pair acceptance is a fundamental trait of a Lewis acid.
Lewis Base
Conversely, a Lewis base is an electron pair donor, which allows them to bond with Lewis acids. These bases possess at least one lone pair of electrons which are not involved in bonding but can be shared.

In the exercise, NH3 is identified as a Lewis base because it has a lone pair of electrons on the nitrogen atom. This lone pair is what NH3 donates to the silver ion, Ag+, illustrating its role as a Lewis base by forming a coordinate bond.
Electron Pair Acceptor
The term 'electron pair acceptor' is synonymous with a Lewis acid. These are most often positively charged or neutral molecules with vacant orbitals that can accommodate additional electrons.

AlBr3 demonstrates this by accepting a pair of electrons from the lone pair on NH3, earning its title as the electron pair acceptor in reaction b from the exercise. The central aluminum atom, due to its trivalent nature, is inherently electron-deficient and can expand its valence shell to accept electron pairs.
Electron Pair Donor
The 'electron pair donor' is another name for a Lewis base. Electron pair donors usually have lone pairs that can be shared with other atoms or ions to create a bond.

The fluoride ion, F-, in reaction c from the exercise, acts as an electron pair donor. It has a spare pair of electrons that it donates to the electron deficient BF3, a Lewis acid, thereby forming a tetrafluoroborate ion, BF4-.
Coordination Complexes
Coordination complexes are structures that result when a Lewis acid bonds with one or multiple Lewis bases. These complexes are a central atom, typically a metal ion, surrounded by several molecules or ions called ligands.

In each of the reactions from the exercise, a coordination complex is formed between the Lewis acid and Lewis base. Ag(NH3)2+ and H3NAlBr3 are examples of coordination complexes where metal ions (Ag+ and Al3+) serve as the central atoms and ammonia (NH3) acts as a ligand, donating its electron pairs to satisfy the electron deficiency of the metal ions.

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

Morphine has the formula C17H19NO3. It is a base and accepts one proton per molecule. It is isolated from opium. A 0.682-g sample of opium is found to require 8.92 mL of a 0.0116 M solution of sulfuric acid for neutralization. Assuming that morphine is the only acid or base present in opium, calculate the percent morphine in the sample of opium.

Answer the following in a complete sentence or two: a. How do you know if an acid is strong or weak? b. How do you calculate the pH of a strong acid? c. How do you calculate the pH of a weak acid solution? d. If you know the Ka of an acid, how do you determine the Kb of its conjugate base? e. If you know [OH-] for a solution, how do you determine [H3O+]?

Find the pH and percent ionization of each HF solution. (Ka for HF is 6.8 * 10-4.) a. 0.250 M HF b. 0.100 M HF c. 0.050 M HF

What is a general characteristic of a Lewis acid? Of a Lewis base?

Determine the pH of each solution. a. 0.0100 M HClO4 b. 0.115 M HClO2 c. 0.045 M Sr(OH)2 d. 0.0852 M KCN e. 0.155 M NH4Cl
See all solutions

Recommended explanations on Chemistry Textbooks

Inorganic Chemistry

Read Explanation

Chemistry Branches

Read Explanation

Chemical Reactions

Read Explanation

Physical Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation

Ionic and Molecular Compounds

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