Periodic Table Trends

Atomic Radius Half the distance between the nuclei of two identical atoms bonded together

Atomic Radius

Atomic Radius Across a Period= DECREASES Down a Group=INCREASES As you add more protons, the attractive force of the nucleus increases, pulling electrons in more closely Down a Group=INCREASES As you add more energy levels, the size of the electron cloud increases

Which of the elements would have the largest radius? 13-Aluminum 14-Silicon 17-Chlorine 12- Magnesium 16-Sulfur 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Ionization Energy The energy required to remove one electron from a neutral atom. High I.E. – Harder to lose electrons Low I.E. –Easier to lose

Ionization Energy

Ionization Energy Across a Period=INCREASES Down a Group=DECREASES Electrons are closer to nucleus, therefore harder to remove Down a Group=DECREASES Electrons are farther from the nucleus, therefore easier to remove

Which element would have the lowest ionization energy? 20- Calcium 56- Barium 4- Beryllium 38- Strontium 12-Magnesium 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Electron Affinity The energy released when a neutral atom acquires an electron. Elements that really want another electron tend to release more energy (higher E.A.) Across a period= INCREASES Down a group= DECREASES

Electronegativity The ability of an atom to attract electrons The most electronegative element is fluorine Across a Period= INCREASES Down a Group= DECREASES

Which of the elements would have the highest electronegativity? 13-Aluminum 14-Silicon 17-Chlorine 12- Magnesium 16-Sulfur 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Ionic Radius Cations- Smaller than atomic radius Anions- Larger than atomic radius

Which of the following would have the larger radius? 17-Chlorine 17-Chlorine Ion 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Which of the following would have the larger radius? 11-Sodium 11-Sodium Ion 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Which of the following would have the smaller radius? 3-Lithium 3-Lithium Ion 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Fluorine Francium METALS vs NONMETALS NONMETALLIC CHARACTER High I.E. (don’t want to lose e-) High E.N. (tend to gain e-) Dull (no luster) Poor Conductors Brittle as solids MOST NONMETALLIC ELEMENT: METALLIC CHARACTER Lower I.E. (tend to lose e-) Lower E.N. (don’t want e-) High Luster (shiny!) Good Conductors Malleable and Ductile MOST METALLIC ELEMENT: Francium Fluorine

Which of the elements would be the least reactive metal? 13-Aluminum 14-Silicon 17-Chlorine 12- Magnesium 16-Sulfur 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Which of the elements would be the most reactive nonmetal? 13-Aluminum 14-Silicon 17-Chlorine 12- Magnesium 16-Sulfur 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

37-Rubidium would have all of the following characteristics except? High Conductivity High Malleability High Brittleness Solid at Room Temperature 1 Valence Electron 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

35-Bromine would have which one of the following characteristics? High Conductivity High Malleability High Brittleness Solid at Room Temperature 7 Valence Electrons 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30