/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 13 Predict the trend in lattice ene... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 12: Problem 13

Predict the trend in lattice energy, from least negative to most negative, for the following compounds based on the ion charges and ionic radii: LiI, LiF; \(\mathrm{CaO}, \mathrm{RbI}\)

Short Answer

Expert verified
The order is: RbI < LiI < LiF < CaO.

Step by step solution

01

Understand Lattice Energy

Lattice energy is the energy required to separate one mole of a solid ionic compound into its gaseous ions. It is influenced by the charge of the ions and the ionic radii. Higher charges and smaller radii result in more negative lattice energy, indicating a stronger attraction and more stability of the compound.
02

Analyze Ion Charges

List the charges of the ions for each compound: - LiI: Li鈦� (charge +1), I鈦� (charge -1) - LiF: Li鈦� (charge +1), F鈦� (charge -1) - CaO: Ca虏鈦� (charge +2), O虏鈦� (charge -2) - RbI: Rb鈦� (charge +1), I鈦� (charge -1) Compounds with ions of higher charges will have more negative lattice energy due to stronger electrostatic forces.
03

Compare Ionic Radii

Consider the ionic radii of the ions: - Iodide (I鈦�) is larger than fluoride (F鈦�). - Lithium (Li鈦�) is smaller than rubidium (Rb鈦�). Ionic radii affect lattice energy; smaller radii result in more negative lattice energy due to the ions being closer together.
04

Predict the Lattice Energy Order

Based on the ion charges and ionic radii: - CaO will have the most negative lattice energy because it has the highest charges (+2 and -2) and relatively small radii. - LiF will be the next, due to its small ionic sizes despite having lower charges (+1 and -1). - LiI and RbI both have charges of +1 and -1. LiI has smaller ions compared to RbI, leading to more negative lattice energy. Thus, the order from least negative to most negative lattice energy is: RbI < LiI < LiF < CaO.

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.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

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

Ionic Compounds
Ionic compounds are a type of chemical compound composed of ions held together by ionic bonds. These compounds form when a metal donates an electron to a non-metal, creating positive and negative ions.
For example, in lithium iodide (LiI), lithium (Li) donates an electron to iodine (I), forming Li鈦� and I鈦� ions.
The fundamental attraction in ionic compounds lies in the electrostatic forces that hold these opposite charges together.
  • Ionic compounds are usually solid at room temperature.
  • They have high melting and boiling points because of the strong bonds between the ions.
  • In solution or molten form, they conduct electricity due to ion mobility.
Understanding these properties is critical when analyzing lattice energy and the stability of compounds.
Ion Charges
Ion charges are fundamental when determining the properties of ionic compounds, such as lattice energy.
Each ion in a compound has a specific charge, either positive or negative, which is determined by the loss or gain of electrons.
Higher ion charges lead to stronger attractions between ions in a compound.
  • In our examples, the ion Ca虏鈦� in calcium oxide (CaO) has a charge of +2, while O虏鈦� has a charge of -2.
  • The larger the ion charge, the greater the electrostatic force between them, leading to more negative lattice energy.
  • These charges are not just theoretical numbers; they reflect how strongly the ions interact with each other.
Remember, high charges mean stronger interactions and generally more stable compounds.
Ionic Radii
Ionic radii refer to the size of an ion, which impacts the distance between ions in an ionic compound.
The size of the ions influences how close they can pack together, thereby affecting the lattice energy.
Generally, smaller ions mean a stronger attraction due to shorter distances between them.
  • In compounds like lithium fluoride (LiF), the small size of fluoride (F鈦�) compared to iodide (I鈦�) results in a more negative lattice energy.
  • Similarly, lithium (Li鈦�) is smaller than rubidium (Rb鈦�), affecting how closely they can sit next to their negative counterparts.
  • Understanding these sizes helps explain why some compounds have stronger bonds than others.
Ionic radii and ion charges together give a complete picture of ion interactions within a compound.
Electrostatic Forces
Electrostatic forces are the key to understanding why ions form bonds in ionic compounds.
These forces originate from the attraction between positively and negatively charged ions in the compound.
The strength of this attraction is determined by two main factors: the magnitudes of the ion charges and the distances between the ions.
  • When ion charges are high, such as in CaO (with charges of +2 and -2), electrostatic forces are stronger.
  • Similarly, smaller distances due to smaller ionic radii result in stronger electrostatic forces.
  • Stronger electrostatic forces correspond to more negative lattice energy, which implies more stable ionic compounds.
By examining these forces, one can predict the properties and stability of different ionic compounds.

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

If your air conditioner is more than several years old, it may use the chlorofluorocarbon \(\mathrm{CCl}_{2} \mathrm{F}_{2}\) as the heat transfer fluid. The normal boiling point of \(\mathrm{CCl}_{2} \mathrm{F}_{2}\) is \(-29.8^{\circ} \mathrm{C},\) and the enthalpy of vaporization is \(20.11 \mathrm{kJ} / \mathrm{mol} .\) The gas and the liquid have molar heat capacities of \(117.2 \mathrm{J} / \mathrm{mol} \cdot \mathrm{K}\) and \(72.3 \mathrm{J} / \mathrm{mol} \cdot \mathrm{K},\) respectively. How much energy is evolved as heat when \(20.0 \mathrm{g}\) of \(\mathrm{CCl}_{2} \mathrm{F}_{2}\) is cooled from \(+40^{\circ} \mathrm{C}\) to \(-40^{\circ} \mathrm{C} ?\)

Benzene, \(\mathrm{C}_{6} \mathrm{H}_{6},\) is an organic liquid that freezes at \(\left.5.5^{\circ} \mathrm{C} \text { (Figure } 11.1\right)\) to form beautiful, feather-like crystals. How much energy is evolved as heat when \(15.5 \mathrm{g}\) of benzene freezes at \(5.5^{\circ} \mathrm{C} ?\) (The enthalpy of fusion of benzene is \(9.95 \mathrm{kJ} / \mathrm{mol} .\) ) If the \(15.5-\mathrm{g}\) sample is remelted, again at \(5.5^{\circ} \mathrm{C},\) what quantity of energy is required to convert it to a liquid?

Elemental silicon and carbon (in the diamond allotropic form) have the same solid-state structure. However, diamond is an insulator and silicon is a semiconductor. Explain why there is a difference.

Identify the following as either \(p\) - or \(n\) -type semiconductors. (a) germanium doped with arsenic (b) silicon doped with phosphorus (c) germanium doped with indium (d) germanium doped with antimony

Two identical swimming pools are filled with uniform spheres of ice packed as closely as possible. The spheres in the first pool are the size of grains of sand; those in the second pool are the size of oranges. The ice in both pools melts. In which pool, if either, will the water level be higher? (Ignore any differences in filling space at the planes next to the walls and bottom.)
See all solutions

Recommended explanations on Chemistry Textbooks

Nuclear Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation

Making Measurements

Read Explanation

Ionic and Molecular Compounds

Read Explanation

Chemical Analysis

Read Explanation

Chemical Reactions

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.