GENERAL CHEMISTRY PRINCIPLES AND MODERN APPLICATIONS ELEVENTH EDITION

The Periodic Table and Some Atomic Properties Slide 9 - 2 CONTENTS 9 -1

9 -1 Classifying the Elements: The Periodic Law and the Periodic Table 1869 Dimitri

Mendeleev’s Periodic Table Mendeleev’s periodic table (1871) Slide 9 - 4 General Chemistry: Chapter

FIGURE 9 -1 An illustration of the periodic law – variation of atomic volume

Slide 9 - 6 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Atomic Number as the Basis for the Periodic Law Moseley 1913 X-ray emission is

FIGURE 9 -2 Schematic of an X-ray tube and Moseley’s X-ray spectra of several

Description of a Modern Periodic Table: The Long Form Slide 9 - 9 General

9 -2 Metals and Nonmetals and Their Ions Metals Good conductors of heat and

Noble Gases Main-Group Metal Ions Metals tend to lose electrons to attain noble gas

Slide 9 - 12 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Main-Group Nonmetal Ions Nonmetals tend to gain electrons to attain noble-gas electron configurations Slide

Transition Metal Ions A few transition metal atoms acquire noble-gas electron configurations when forming

Hydrogen H atom (1 s 1) Usually loses one electron, but can gain one,

9 -3 Sizes of Atoms and Ions Atomic Radius Covalent radius is one half

FIGURE 9 -3 Sizes of Atoms and Ions Slide 9 - 17 General Chemistry:

Screening and Penetration FIGURE 9 -4 Atomic radii Slide 9 - 18 General Chemistry:

FIGURE 9 -5 Radial distribution functions for aluminum Slide 9 - 19 General Chemistry:

FIGURE 9 -6 The shielding effect and effective nuclear charge, Zeff Slide 9 -

FIGURE 9 -7 Effective nuclear charges. Zeff, of valence electrons Slide 9 - 21

FIGURE 9 -8 Variation of effective nuclear charge and percent screening Slide 9 -

FIGURE 9 -9 The average distance from the nucleus for the least strongly bound

9 -3 Sizes of Atoms and Ions Ionic Radius FIGURE 9 -10 A comparison

Ionic Radius Cations are smaller than the atoms from which they are formed. For

FIGURE 9 -11 A comparison of some atomic and ionic radii Slide 9 -

9 -4 Ionization Energy Mg(g) → Mg+(g) + e− I 1 = 738 k.

FIGURE 9 -12 First ionization energies as a function of atomic number Slide 9

With relatively few exceptions, ionization energies increase from left to right across a period

Slide 9 - 30 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Slide 9 - 31 FIGURE 9 -13 Orbital diagrams showing the valence electron configurations

FIGURE 9 -14 First ionization energies of the third row p-block elements Slide 9

9 -5 Electron Affinity F(g) + e− → F−(g) EA = − 328 k.

Values are in kilojoules per mole for the process X(g) + e– X–(g). FIGURE

FIGURE 9 -16 Electron affinities of some of the main group elements Slide 9

The Second Electron Affinity is positive due to the strong repulsive force between the

9 -6 Magnetic Properties Diamagnetic atoms or ions: All e− are paired. Weakly repelled

Paramagnetism Slide 9 - 38 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada

9 -7 Polarizability FIGURE 9 -17 Polarization of an atom Slide 9 - 39

Polarizability increases with the size of the atom. Slide 9 - 40 General Chemistry:

FIGURE 9 -18 Polarizabilities and atomic volumes Slide 9 - 41 General Chemistry: Chapter

FIGURE 9 -19 Atomic properties and the periodic table – a summary Slide 9

End of Chapter Slide 9 - 43 General Chemistry: Chapter 9 Copyright © 2017

Slides: 43

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GENERAL CHEMISTRY PRINCIPLES AND MODERN APPLICATIONS ELEVENTH EDITION PETRUCCI HERRING MADURA BISSONNETTE The Periodic Table and Some Atomic Properties 9 PHILIP DUTTON UNIVERSITY OF WINDSOR DEPARTMENT OF CHEMISTRY AND BIOCHEMISTRY Slide 9 - 1 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

The Periodic Table and Some Atomic Properties Slide 9 - 2 CONTENTS 9 -1 Classifying the Elements: The Periodic Law and the Periodic Table 9 -2 Metals and Nonmetals and Their Ions 9 -3 Sizes of Atoms and Ions 9 -4 Ionization Energy 9 -5 Electron Affinity 9 -6 Magnetic Properties 9 -7 Polarizability General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

9 -1 Classifying the Elements: The Periodic Law and the Periodic Table 1869 Dimitri Mendeleev Lothar Meyer When the elements are arranged in order of increasing atomic mass, certain sets of properties recur periodically. Dimitri Mendeleev (1834 -1907) Slide 9 - 3 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Atomic Number as the Basis for the Periodic Law Moseley 1913 X-ray emission is explained in terms of transitions in which e− drop into orbits close to the atomic nucleus. Correlated frequencies to nuclear charges. = A (Z – b)2 Used to predict new elements (43, 61, 75) later discovered. Henry G. J. Moseley (1887 -1915) Slide 9 - 7 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

9 -2 Metals and Nonmetals and Their Ions Metals Good conductors of heat and electricity. Malleable and ductile. Moderate to high melting points. Nonmetals Nonconductors of heat and electricity. Brittle solids. Some are gases at room temperature. Metalloids Metallic and non-metallic properties Slide 9 - 10 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Transition Metal Ions A few transition metal atoms acquire noble-gas electron configurations when forming cations, but most do not. Slide 9 - 14 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Hydrogen H atom (1 s 1) Usually loses one electron, but can gain one, to attain a noble gas configuration. Is often placed in Group 1, but sometimes in Group 17. H 2 is a reducing agent (compare to F 2, or Cl 2) Slide 9 - 15 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

9 -3 Sizes of Atoms and Ions Atomic Radius Covalent radius is one half of the distance between the nuclei of two identical atoms joined by a single covalent bond. Ionic radius is based on the distance between the nuclei of ions joined by an ionic bond. (properly apportioned by assigning r(O 22–) = 140 pm) Metallic radius is one-half the distance between the nuclei of two atoms in contact in the crystalline solid metal. van der Waals radius is similar to metallic radius except is for solid samples of noble gases. Slide 9 - 16 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Ionic Radius Cations are smaller than the atoms from which they are formed. For isoelectronic cations, the more positive the ionic charge, the smaller the ionic radius. Anions are larger than the atoms from which they are formed. For isoelectronic anions, the more negative the charge, the larger the ionic radius. Slide 9 - 25 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

With relatively few exceptions, ionization energies increase from left to right across a period and decrease from top to bottom within a group. Ionization energies decrease as atomic radii increase. Slide 9 - 29 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

9 -5 Electron Affinity F(g) + e− → F−(g) EA = − 328 k. J F(1 s 22 p 5) + e− → F−(1 s 22 p 6) electron affinity, Ea, can be defined as the enthalpy change, ∆ea. H, that occurs when an atom in the gas phase gains an electron Slide 9 - 33 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

Values are in kilojoules per mole for the process X(g) + e– X–(g). FIGURE 9 -15 Electron affinities of main-group elements Slide 9 - 34 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

The Second Electron Affinity is positive due to the strong repulsive force between the electron and the ion. Slide 9 - 36 O(g) + e− → O−(g) EA = − 141 k. J O−(g) + e− → O 2−(g) EA = +744 k. J General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.

9 -6 Magnetic Properties Diamagnetic atoms or ions: All e− are paired. Weakly repelled by a magnetic field. Paramagnetic atoms or ions: Unpaired e −. Attracted to an external magnetic field. Slide 9 - 37 General Chemistry: Chapter 9 Copyright © 2017 Pearson Canada Inc.