Trends of the Periodic Table Exceptions, shortcuts and periodic trends (6.3)

Learning Targets You will: Know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity Determine how to write electron configuration and orbital notation for atoms and ions. Compare and contrast atoms and ions based on periodic trends.

Exceptions Chromium (Cr) and copper (Cu) Completely full or half full d sublevel is more stable than a partially filled d sublevel Cr (expected): 1s2 2s2 2p6 3s2 3p6 4s2 3d4 Cr: 1s2 2s2 2p6 3s2 3p6 4s1 3d5 Cu (expected): 1s2 2s2 2p6 3s2 3p6 4s2 3d9 Cu: 1s2 2s2 2p6 3s2 3p6 4s1 3d10 You will determine how to write electron configuration and orbital notation for atoms and ions.

Noble Gas Configuration An example of this (Gallium): full: 1s22s22p63s23p64s23d104p1 noble gas short cut: [Ar] 4s23d104p1 The noble gas that precedes the element is the noble gas used in the shortcut. Its electron configuration is replaced with the noble gas in brackets. Remaining electron configuration is written after. Noble gases = group of elements w/filled electron cloud Found in group 8 or 18 Stable and relatively inert or unreactive Easier way to write a full configuration

Examples Answers: Br: [Ar]4s23d104p5 Sn: [Kr]5s24d105p2 Write the electron configuration using the noble gas shortcut for: bromine (Br) tin (Sn) pollonium (Po) fluorine (F) Answers: Br: [Ar]4s23d104p5 Sn: [Kr]5s24d105p2 Po: [Xe]6s24f145d106p4 F: [He]2s22p5

Examples

Try on your own Answers: Si: [Ne]3s23p2 Pb: [Xe]6s24f145d106p2 Write the electron configuration using the noble gas shortcut for: silicon (Si) lead (Pb) iodine (I) cesium (Cs) Answers: Si: [Ne]3s23p2 Pb: [Xe]6s24f145d106p2 I: [Kr]5s24d105p5 Cs: [Xe]6s1

Try on your own

Isoelectronic Ions Atoms or ions that have the same electronic structure http://www.iun.edu/~cp anhd/C101webnotes/ch emical- bond/isoelectronic.html You will determine how to write electron configuration and orbital notation for atoms and ions.

Practice Write the electron configuration for the magnesium ion. Write the electron configuration for the phosphorus ion. 1s2 2s2 2p6 1s2 2s2 2p6 3s2 3p6 You will determine how to write electron configuration and orbital notation for atoms and ions.

Try on your own Write the electron configuration for neon. Name one positive ion and one negative ion with the same configuration. 1s2 2s2 2p6 Na+, Mg2+, Al3+, N3-, O2-, F- You will determine how to write electron configuration and orbital notation for atoms and ions.

You will compare and contrast atoms and ions based on periodic trends. Valence Electrons Electrons in the outermost (highest) principal energy level of an atom Important for atom bonding Number corresponds to group number (except He) You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Examples The halogens contain how many valence electrons? Sodium has how many electrons in its outermost principal energy level? The alkali earth metals have how many valence electrons? The noble gases contain how many valence electrons? 7 1 2 8 You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

Atomic Size (also radii and radius) Measure of atom size Extremely small, often measured in picometers (pm) Typical distance from center of nucleus to boundary of electron cloud Increases moving to left on period Increases moving down a group You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

Atomic Size (also radii and radius) You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Examples Which of the following atoms has the largest atomic radius? (Na, Mg, Si, P) Which of the following atoms has the smallest atomic radius? (As, Sb, Bi, P) Which of the following has the largest atomic radius? (Na, Mg, P, N) Which of the following has the smallest atomic radius? (N, F, Br, Cl) Na P F You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Ionic Radii Closely linked to atomic radii Neutral atom gains or loses electrons creating anions or cations Depending on that loss or gain, atom’s radius increases or decreases You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Ionic Radii You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Ionization Energy Energy required to remove an electron, loosely bound valence electron, from an individual atom in the gas phase Energy required to remove first electron is called first ionization energy Increases moving across a period Increases moving up a group You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Ionization Energy You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Interpret Data What are the values for the first, second and third ionization energies for sodium and aluminum? Is it easier to remove an electron from a sodium (Na) or aluminum (Al) atom? From Na+ or Al+? From Na2+ or Al3+? Which ion is more common – Na3+ or Al 3+? You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Examples Which of the following has the highest ionization energy? (Ca, C, N, O) Which of the following atoms has the highest ionization energy? (Mg, Si, P, Cl) Which of the following atoms has the highest ionization energy? (Al, Si, P, As) O Cl P You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Electronegativity Measure of an atom’s tendency to attract shared electrons Pauling scale used Fluorine is the most electronegative atom Increases moving across period Increases moving up a group You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Electronegativity You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. Electron affinity A neutral atom’s likelihood of gaining an electron The less valence electrons, the least likely an atom will gain electrons Increases across a period Increases up a group You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

You will compare and contrast atoms and ions based on periodic trends. All the trends … You will know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity You will compare and contrast atoms and ions based on periodic trends.

Learning Targets You will: Know the trends of the periodic table: atomic radii, ionic radii, electronegativity, ionization energy, electron affinity Determine how to write electron configuration and orbital notation for atoms and ions. Compare and contrast atoms and ions based on periodic trends.