9.10.12. Bohr Models and Valence Electrons

Bohr Model and Valence Electrons Identifying Trends Along the Periodic Table (part 2)

Bohr Model part 2 Do First: 1. SW take out HW and analyze Lithium for identification of Bohr Model. a. "Today we will begin class by analyzing Lithium. How many electrons does Lithium have? S response: "3" b. Everyone look at Lithium's outermost shell. How many electrons are hanging out in its outermost shell? S response: "1"

Bohr Model part 2 Valence electrons are the special name given to electrons located in an element's outermost shell. Remember Lithium? Lithium has ___ valence electron (S response: 1). Everyone look at their homework again. Find Beryllium.

How many valence electrons does Beryllium have? _____. Confirm and re-explain at your table. (Answer: ___)

Bohr Model part 2 Why is learning about valence electrons so important?

It is because the number of valence electrons will determine if an element is most reactive or most stable. Valence electrons determine reactivity!

Ex: Since Lithium has one valence electron, it is most reactive since it is an alkali metal. It needs 7 more valence electrons to be stable.

Bohr Model part 2 Look at Neon from your HW. How many valence electrons does it have? Neon has 8 valence electrons. This means that because its electron shell is full, it is the most unreactive or the MOST STABLE. *You can remember this as if it's Thanksgiving. If you are full, you are unreactive.*

Bohr Model part 2 What can you tell me about the reactivity as you go across a period? ______________________________________ ______________________________________ How do you know? ______________________________________ ______________________________________

Bohr Model 2 http://www.brainpop.com/science/matterandchemistry/ions/

Bohr Model-part 2 GP / IP- Stations Table 1 - HW Check Table 2 (HW) - Bohr Model Practice (11-18) Table 3- Valence Electron Calculations Table 4- Period Trends and Group Trends Table 5- Reactivity vs. Stability Table 6- Am I a metal, metalloid, halogen, or a noble gas?

Table 7- Ions part 1

Bohr Model part 2 HW- Complete Bohr Models for elements that have atomic numbers 15-18. Highlight all valence electrons for each as well.