Chapter 3: Problem 33
Which relation represent the correct relationship of the radius of an atom, its cation and its anion? (1) atom \(=\) cation \(=\) anion (2) atom \(>\) cation \(>\) anion (3) atom \(>\) cation \(<\) anion (4) atom \(<\) cation \(>\) anion
Short Answer
Expert verified
Option (3): atom > cation < anion
Step by step solution
01
Understand Atomic Radius
The atomic radius is the distance from the nucleus to the outermost electron cloud of an atom in its neutral state.
02
Understanding Cation
A cation is formed when an atom loses one or more electrons, resulting in a positive charge. The loss of electrons reduces electron-electron repulsion in the outer shell, pulling electrons closer to the nucleus and thus decreasing the atomic radius.
03
Understanding Anion
An anion is formed when an atom gains one or more electrons, resulting in a negative charge. The addition of electrons increases electron-electron repulsion among the outer electrons, pushing them further from the nucleus and thus increasing the atomic radius.
04
Compare Atomic Radii
By considering the changes in electron configuration and repulsion, the radius of an atom decreases when it forms a cation and increases when it forms an anion. Thus, the correct relationship of the radii is: atom > cation < anion.
05
Select the Correct Option
Compare the findings with the provided options. The correct relationship is represented by option (3): atom > cation < anion.
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 Vaia!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Atomic Radius
The atomic radius of an atom is the distance from its nucleus to the outermost boundary of the electron cloud. This distance determines how large the atom is. Understanding the atomic radius helps us to compare the sizes of different atoms and ions.
The size of the atomic radius depends on:
The size of the atomic radius depends on:
- The number of protons in the nucleus, which pull electrons closer
- The number of electron shells, as more shells mean a larger radius
Cation Size
A cation is an atom that has lost one or more electrons, resulting in a positive charge. When an atom loses electrons to form a cation, the loss occurs from the outermost electron shell.
This loss of electrons has two main effects on the size of the cation:
This loss of electrons has two main effects on the size of the cation:
- Reduction in electron-electron repulsion: With fewer electrons in the outer shell, there is less repulsion pushing the electrons apart, allowing the shell to contract closer to the nucleus.
- Greater effective nuclear charge: The nucleus' positive charge has a stronger pull on the remaining electrons, pulling them inward.
Anion Size
An anion is an atom that has gained one or more electrons, resulting in a negative charge. When an atom gains electrons to form an anion, these extra electrons are added to the outermost electron shell.
This gain of electrons causes the following changes:
This gain of electrons causes the following changes:
- Increased electron-electron repulsion: The additional electrons increase repulsion among the electrons in the outer shell, which causes the shell to expand.
- Lower effective nuclear charge per electron: The same nuclear charge is shared among more electrons, weakening the pull on each individual electron.
Electron Configuration
The electron configuration of an atom or ion describes how electrons are arranged in shells and subshells around the nucleus.
When an atom becomes a cation or anion, its electron configuration changes to reflect the loss or gain of electrons. Here's how:
When an atom becomes a cation or anion, its electron configuration changes to reflect the loss or gain of electrons. Here's how:
- Cations: Electrons are removed from the outermost shell, reducing the overall size and leading to a more compact electron configuration.
- Anions: Electrons are added to the outermost shell, resulting in a larger electron cloud and an expanded configuration.