1. Chem
Get Periodic Table Intro Packet stamped off if you did not do so last time
Today: Periodic Trends

2. Groups you should know by name
Group 1: Alkali Metals
Note: Hydrogen is NOT considered an alkali metal
Group 2: Alkaline Earth Metals
Groups 3-12: Transition Metals
Group 17: Halogens
Group 18: Noble Gases

3. Review…
1. Why do all elements want to be like a noble gas? Noble gases have a full valence shell 2. In terms of electrons, what can elements do to try to become like a noble gas? Lose or gain electrons

4. Periodic Table of Elements
Is organized
By increasing atomic number
Based on elements with similar properties

5. Rows
Each Row is called a period

6. Columns
Each column is called a group or family

7. As you go across a period (left to right):
Does the number of energy levels change?
Do you get closer or further from a noble gas element? NO
CLOSER

8. As you go down a group (top to bottom):
Does the number of energy levels change?
Do you get closer or further from a noble gas element?
YES (increases)
Neither (no change)

9. Periodic Trends
A periodic trend is a pattern for a specific characteristic of an element that is observed in the periodic table. These trends are general and have their exceptions.

10. Atomic Radius
A measure of the size of an atom

11. Electronegativity
A measure of an atom’s ability to gain or attract electrons
Can be thought of as an atom’s desire or greediness for electrons (“greedy like the Grinch”)

12. Ionization Energy
The amount of energy required to remove an electron from the outermost shell of an atom
A measure of an atom’s ability to lose an electron and form a cation

13. Practice: Looking up Values in the Reference Table
1. Look up the atomic radius for Mg and Ca. Which one has a greater atomic radius? ) Mg 2) Ca
140
174

14. Practice: Looking up Values in the Reference Table
2. Look up the electronegativity for Mg and Ca. Which one has a greater electronegativity? 1) Mg 2) Ca
1.3
1.0
It’s easier for Mg to gain electrons than Ca

15. Practice: Looking up Values in the Reference Table
3. Look up the ionization energy for Mg and Ca. Which one has a greater ionization energy?
1) Mg 2) Ca
738
590
It’s easier for Ca to lose electrons than Mg (requires less energy to remove it)

16. Periodic Trends War
Get into groups of 4. Distribute the cards so that everyone has ONE card that is numbered 1-6
For each round, you will be comparing your element cards and a specific value from the reference table.
As a group, order the cards from smallest value to largest value. Then, determine who wins the round based on who has the greatest value for the trend you are looking at for this turn.
Fill in each row of the following table as you complete each round

18. Teams
Kelby, Jackson, Lily
Garrett, Isa, Gabe,