1. Activity 17: Modeling Molecules Warm up: How many protons does Mg have? How many electrons? How many of them are valence electrons? How many neutrons? Switching seats!

2. Activity 17: Modeling Molecules

3. Activity 16 Extension Answers

4. Activity 16 In Case You Missed It... Dmitri Mendeleev was a Russian scientist; he organized the periodic table based on their properties. Atomic number- corresponds with the order on the periodic table; also equal to the number of protons. Atomic mass- the number of protons and the number of neutrons added together.

5. Activity 16 In Case You Missed It... Electrons are equal to the number of protons in an atom.

6. Activity 16 In Case You Missed It... Chemical formula- shorthand way to identify the kind and number of atoms that make up a compound. – Ex: NaCl is sodium chloride. Matter can be classified into elements (pure substances), compounds (two or more substances chemically bonded), and mixtures (can be separated by physical means, like sand and salt)

7. My mistake! My mistake! ION- atom with an overall electric charge due to a lack or gain of electron- not ISOTOPE! So sorry If an atom of oxygen loses 3 electrons, what charge does the ion have?

8. Quiz!

9. Activity 17: Modeling Molcules Please open your books to page B31

10. Why do chemicals bond? Chemicals form bonds to obtain full outer electron shells. – How many electrons can fit in the first shell? – The second? – All chemicals want to look like noble gases; they want to have their outer shells filled. All electron shells are full

11. Activity 17: Modeling Molecules Procedure is on the lab table. FOLLOW IT CAREFULLY. Activity 17 Handout Be sure to sketch your molecule models after you create them at your table!

12. Drawing the Diagrams: 20 points

13. Activity 17: Modeling Molecules Following the directions, complete Activity 17. I am collecting your sheets for a grade! When you get to step 6, it is on my desk up front. Step 11: only do 2 molecules (it says 4) and draw it on the back of the paper!

14. Valence Electrons and Families

15. Two Types of Chemical Bonds Covalent bond- when 2 atoms share a pair of electrons. Only occurs between 2 non-metals.

16. Two Types of Chemical Bonds Ionic bond- the complete transfer of valence electrons between atoms. Only occurs between a metal and non-metal. – One atom totally gives up its valence electron(s) to another while the other gains it.

17. Tonight’s Homework Complete Activity 17 Analysis – #6 is an UC assessment! Scoring guide and prompt in Content Library May be done on paper! Also: Given that nitrogen forms 3 bonds with hydrogen to make NH 3, how many hydrogen atoms do you think will bond with an atom of phosphorus?