Catalyst: Complete the Chart

1. Catalyst: Complete the Chart Hint: According to the octet rule, atoms lose or gain electrons, forming ions, in order to get a full outer shell with 8 electrons. If the atom loses electrons it is a positive cation and if it gains electrons it is a negative anion.

2. Catalyst: Answers Hint: According to the octet rule, atoms lose or gain electrons, forming ions, in order to get a full outer shell with 8 electrons. If the atom loses electrons it is a positive cation and if it gains electrons it is a negative anion.

3. TODAY’S OBJECTIVE:BONDING!!!!SWBAT Differentiate between IONIC &COVALENT BONDS A.K.A.: Why don’t you blow up when you eat sodium chloride since sodium is a highly reactive metal and chlorine is an extremely poisonous gas??

4. Agenda • Catalyst/HW Check (10) HW Review (10) Part 1: Ionic Compound Formula Review: Kris-Kross Method (20) PART 2: Ionic vs. Covalent Compounds • Ionic vs. Covalent Notes (20) • Ionic vs. Covalent Lab (40) • Ionic vs. Covalent Conductivity Demo (10) • Closing (5)

5. Homework Answers • Having equal amounts of positive and negative charge is called electroneutrality. • An electrically charged group of two or more bonded atoms that functions as a single ion is a polyatomic ion. • Collections of cations are never found without a similar number of anions (or sometimes electrons) nearby to effectively neutralize the charges. • The names for cations come from the element from which they are formed. • When an element forms two or more positive ions, the ions are distinguished by using roman numerals to indicate the charge. • The name of a simple anion is formed by changing the ending of the element name to –ide. • A subscript is a whole number written below and to the right of an element’s symbol, and it is used to denote the number of atoms in a formula. • Any chemical compound that is composed of oppositely charged ions is called an ionic compound.

6. More HW Answers • K+ + Br- → KBr • Ba2+ + F- → BaF2 (2 F- to balance 2+ charge) • Sn4+ + O2- → SnO2 (2 O2- to balance 4+) • Cs2+ + Br- → CsBr2 (2 Br- to balance 2+) The rest of the problems are coming up as practice…

7. Writing Ionic Compound Formulas Notes

8. Ca2+As3- Kris Kross Method! Ca3As2

9. Just kris kross the positive and the negative charges Na1+Cl1- NaCl Pb4+O2- Pb2O4

10. Practice Problems • What ionic compound is formed? • Cobalt (II) and Bromine • Mercury(I) and Sulfur • Aluminum and Iodine Hints: • Periodic table groups tell us how many valence electrons • Draw Lewis structure • Metals lose electrons to form positive cations • Nonmetals gain electrons to form negative anions • Compounds must be neutral (equal # of + and – charges)

11. Part 2! Ionic vs. Covalent Bonds • Make a Chart in your notes that looks like this:

12. Ionic vs. Covalent Bonds • Bond Strength = the energy needed to break the bonds between atoms in a compound.

13. Ionic vs. Covalent Bonds

14. Ionic vs. Covalent Bonds

15. Ionic vs. Covalent Bonds Water (H2O) molecules Lithium Chloride (LiCl) crystal lattice

16. Ionic vs. Covalent Bonds

17. Ionic vs. Covalent Bonds

18. Ionic vs. Covalent Bonds

19. Investigation: Ionic vs. Covalent • You will work in groups of 4. (2 groups per table) • Lab WS is due at end of class • Safety! Do not put any test substances near your eyes or mouth. • Clean Up: Pour liquids down the sink and solids in the trash. • Objective: Conduct four tests on four substances. Predict whether they are ionic or covalent. • Ms. Boon will run the conductivity test.

20. Exit Slip • What is the formula for a compound between: Ca & F? • Compare at least one difference between ionic & covalent compounds? • Does the compound MgBr2 share electrons or transfer them between the atoms?

21. 3 Types of Bonding

22. Practice- Ionic or covalent? • SH6 • KCl • H3C3O2 • N2 • CsBr • HF • CaCl2 • H2 • MgCl2 • NH3 • Li2S • Cl2 • H2O • Na3P • BaS