1. Periodic Trends refer to patterns of properties that exist as elements are considered from one end of the table to the other Trend in atomic number left to right across a Periodatomic number increases bottom to top up a Groupatomic number decreases Atomic Radius is defined as ____________________________ ___________________________________________________ Top to bottom DOWN a Group Atomic radius ____________ due to an increase in the number of electron shells Left to right ACROSS a Period Atomic radius ____________ due to an increase in nuclear charge

2. To determine an element with the largest or smallest radius largest radius – farthest left and farthest down smallest radius – farthest right and farthest up Metallic and Nonmetallic Properties Elements on the bottom left of the table have more metallic properties, but less nonmetallic properties Elements on the top right have more nonmetallic properties and less metallic properties Top to bottom DOWN a Group Metallic properties ______________ and nonmetallic properties ________________ Left to right ACROSS a Period Metallic properties _________________ and nonmetallic properties _________________

3. To determine which element from the given choices has greatest metallic characteristics OR least nonmetallic characteristics Consider the location of each element on the Periodic table and choose the element farthest left and/or closest to the bottom To determine which element given has the least metallic properties OR greatest nonmetallic properties Consider the location of each element on the Periodic table and choose the element farthest right and/or closest to the top

4. Electronegativity defines ______________________________ __________________________________________________ Fluorine is assigned the highest electronegativity value of 4. Cesium and Francium are assigned the lowest value of 0.7. Ionization Energy refers to _____________________________ __________________________________________________ The alkali metals in Group 1 tend to have the lowest ionization energy. The noble gases have the highest ionization energy values.

5. Top to bottom DOWN a Group Electronegativity ____________________ Ionization Energy ____________________ Left to right ACROSS a Period Electronegativity _____________________ Ionization Energy _____________________ To determine which element has the greatest attraction for electrons Choose elements with the HIGHEST electronegativity value To determine which element has the least attraction for electrons Choose elements with the LOWEST electronegativity value

6. To determine which element has the greatest tendency to lose electrons Choose elements with the LOWEST ionization energy value To determine which element has the least tendency to lose electrons Choose elements with the HIGHEST ionization energy value

7. Allotropes refer to _________________________________ ________________________________________________ Differences in molecular structures give allotropes of the same element different physical and chemical properties Examples Oxygen allotropesO 2 and O 3 (ozone) Carbon allotropesdiamond, graphite, and buckminsterfullerene