   Chapter 7, Problem 41GQ

Chapter
Section
Textbook Problem

These questions are not designated as to type or location in the chapter. They may combine several concepts.The red color of rubies is the result of the substitution of some Cr3+ ions for Al3+ ions in solid Al2O3. (a) Using spdf notation with the noble gas notation, write the electron configuration for the Cr atom and for the Cr3+ ion? (b) Is Cr2+ paramagnetic? Is Cr3+? (c) The radius of the Cr3+ ion is 64 pm. How does this compare with the radius of the Al3+ ion?

a)

Interpretation Introduction

Interpretation:

The electronic configuration of Cr and Cr3+ has to be written using spdf notation with nobel gas notation.

Concept Introduction:

Electronic configuration: The electronic configuration is the distribution of electrons (e-) of an given molecule or respective atoms in atomic or molecular orbital’s.

Aufbau principle: This rule statues that ground state of an atom or ions electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels. If consider the 1s shell is filled the 2s subshell is occupied.

Hund's Rule: The every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in singly occupied orbitals have the same spin.

Paramagnetic: The Paramagnetic properties are due to the presence of some unpaired electrons, and from the realignment of the electron paths caused by the external magnetic field.

Diamagnetic properties: In diamagnetic materials all the electron are paired so there is no permanent net magnetic moment per atom.

Explanation

Electronic configuration for (Cr) and (Cr3+) systems:

• Electronic configuration for Cr: The Chromium (Cr) has six electrons in outermost five (3d) orbital and one electron in (4s) orbital, the electrons filling method presented below.

AtomicnumberofChromium (Cr)= 24spdfwith orbtital notation=[1s22s22p63s23p63d54s1]spdfwith noble gas notation=[Ar]3d54s1Orbitalboxnotation       =  [Ar]3d54s1

Hence, the electronic configuration of Chromium is [Ar]3d54s1

• Electronic configuration for Cr3+: When Chromium (Cr) was oxidized to (Cr3+) ions, it lose for three electrons from outermost (4s, 3d) shells

b)

Interpretation Introduction

Interpretation:

The magnetic property of given ions Cr and Cr3+ has to be predicted.

Concept Introduction:

Paramagnetic: The Paramagnetic properties are due to the presence of some unpaired electrons, and from the realignment of the electron paths caused by the external magnetic field.

Diamagnetic properties: In diamagnetic materials all the electron are paired so there is no permanent net magnetic moment per atom.

c)

Interpretation Introduction

Interpretation:

The radius of Al3+ and Cr3+ has to be compared and explained.

Concept Introduction:

Electronic configuration: The electronic configuration is the distribution of electrons (e-) of an given molecule or respective atoms in atomic or molecular orbital’s.

Aufbau principle: This rule statues that ground state of an atom or ions electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels. If consider the 1s shell is filled the 2s subshell is occupied.

Hund's Rule: The every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in singly occupied orbitals have the same spin.

Atomic or ionic radii: The distance between the nucleus and the outer valence electrons of any atom or ion.

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Find more solutions based on key concepts 