Chapter 6 The Periodic Table 6.3 Periodic Trends 6.1 Organizing the Elements 6.2 Classifying the Elements 6.3 Periodic Trends Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in Ionization Energy Atomic Radius – one-half the distance between the nuclei of two atoms of the same element when the atoms are joined. Ionization Energy – energy required to remove one electron from an atom. Electronegativity – ability of an atom of an element to attract electrons when the atom is in a compound. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in Atomic Size Atomic Radius: one-half the distance between the nuclei of two atoms of the same element when the atoms are joined. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in Atomic Size In general, atomic size increases from top to bottom within a group, and decreases from left to right across a period. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in atomic size. Trends in Atomic Size Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Which atom in each pair has the larger atomic radius? Li or K Ca or Ni CHEMISTRY & YOU Which atom in each pair has the larger atomic radius? Li or K Ca or Ni Ga or B O or C Cl or Br f) Be or Ba Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Which atom in each pair has the larger atomic radius? Li or K Ca or Ni CHEMISTRY & YOU Which atom in each pair has the larger atomic radius? Li or K Ca or Ni Ga or B O or C Cl or Br f) Be or Ba Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

HW #38 - Which element in each pair has the larger atomic radius? CHEMISTRY & YOU HW #38 - Which element in each pair has the larger atomic radius? Na or Li Sr or Mg C or Ge Se or O Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

HW #38 - Which element in each pair has the larger atomic radius? CHEMISTRY & YOU HW #38 - Which element in each pair has the larger atomic radius? Na or Li Sr or Mg C or Ge Se or O Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Ions An atom or group of atoms that has a positive or negative charge. Atoms become ions when electrons are lost or gained. Atoms can become cations or anions Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Cation – ion with a positive charge Ions Cation – ion with a positive charge Metals tend to form cations. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Anion – ion with a negative charge Ions Anion – ion with a negative charge Nonmetals tend to form anions. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Cations are always smaller than the atoms from which they form. Trends in Ionic Size Trends in Ionic Size Cations are always smaller than the atoms from which they form. Anions are always larger than the atoms from which they form. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Group Trends in Ionic Size Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

The figure below summarizes the group and period trends in ionic size. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

HW #44 – Which particle has the larger radius in each atom/ion pair? CHEMISTRY & YOU HW #44 – Which particle has the larger radius in each atom/ion pair? Na, Na+ S, S2- I, I- Al, Al3+ Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

HW #44 – Which particle has the larger radius in each atom/ion pair? CHEMISTRY & YOU HW #44 – Which particle has the larger radius in each atom/ion pair? Na, Na+ S, S2- I, I- Al, Al3+ Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in Ionization Energy Ionization Energy – energy required to remove one electron from an atom. The energy to remove the first electron is called the first ionization energy. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Ionization Energies of Some Common Elements Interpret Data Ionization Energies of Some Common Elements Symbol First Second Third H 1312 He (noble gas) 2372 5247 Li 520 7297 11,810 Be 899 1757 14,840 C 1086 2352 4619 O 1314 3391 5301 F 1681 3375 6045 Ne (noble gas) 2080 3963 6276 Na 496 4565 6912 Mg 738 1450 7732 S 999 2260 3380 Ar (noble gas 1520 2665 3947 K 419 3096 4600 Ca 590 1146 4941 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

1. Which has the smallest ionization energy; Trends in Atomic Size Practice Problems 1. Which has the smallest ionization energy; Sodium, Calcium, Potassium, Magnesium 2. List in order of increasing ionization energy (smallest to largest) Beryllium, Cesium, Oxygen, Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #40 - Which element in each pair has a greater first ionization energy? Li or B Mg or Sr Cs or Al Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #40 - Which element in each pair has a greater first ionization energy? Li or B Mg or Sr Cs or Al Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #41 – Arrange the following groups of elements in order of increasing ionization energy. Be, Mg, Sr Bi, Cs, Ba Na, Al, S Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #41 – Arrange the following groups of elements in order of increasing ionization energy. Be, Mg, Sr → Sr, Mg, Be Bi, Cs, Ba → Cs, Ba, Bi Na, Al, S → Na, Al, S Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Electronegativity Values for Selected Elements Interpret Data Electronegativity – ability of an atom of an element to attract electrons when the atom is in a compound. Electronegativity Values for Selected Elements H 2.1 Li 1.0 Be 1.5 B 2.0 C 2.5 N 3.0 O 3.5 F 4.0 Na 0.9 Mg 1.2 Al Si 1.8 P S Cl K 0.8 Ca Ga 1.6 Ge As Se 2.4 Br 2.8 Rb Sr In 1.7 Sn Sb 1.9 Te I Cs 0.7 Ba Tl Pb Bi Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in Electronegativity In general, electronegativity values decrease from top to bottom within a group. For representative elements, the values tend to increase from left to right across a period. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #45 - Which element in each pair has a higher electronegativity value? Cl or F C or N Mg or Ne As or Ca Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #45 - Which element in each pair has a higher electronegativity value? Cl or F C or N Mg or Ne As or Ca Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #47 – When the elements in each pair are chemically combined, which has a greater attraction for electrons? Ca or O O or F H or O K or S Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

CHEMISTRY & YOU HW #47 – When the elements in each pair are chemically combined, which has a greater attraction for electrons? Ca or O O or F H or O K or S Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in Electronegativity Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Mendeleev’s Periodic Table How did Mendeleev organize his periodic table? https://www.youtube.com/watch?v=0RRVV4Diomg Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Trends in Atomic Size Do Now: Without looking at your periodic table, classify each of the following elements K Ca Al F Ar U Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .

Reading the Periodic Table Do Now: Which element has chemical properties similar to Oxygen? Lithium, Neon, Phosphorus, or Sulfur Classify each as metal, metalloid, or nonmetal. Aluminum Silicon Phosphorus Cadmium Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. .