1. Chemical Bonds

2. Ionic Bonding Stable electron configurations Ionic Bonds Ionic Compounds

3. Stable Electron Configurations What do you think this means?

4. Stable Electron Configurations When the highest energy level of an atom is filled with electrons, the atom is stable and not likely to react.

5. Electron Dot Diagrams

6. Model of an atom in which each dot represents a valence electron. In the center is the elemental abbreviation which represents the nucleus and all other electrons in the element.

7. Molecular Models of Hydrogen

11. Figure 9

12. Ionic Bonds Transfer of electrons Formation of ions Formation of ionic bonds Ionization energy

13. Ionic Bonds Some elements achieve stable electron configurations through the transfer of electrons between atoms.

14. Transfer of Electrons The end result of bonding is a stable electron configuration. Sodium Chloride

15. Transfer of Electrons

16. Formation of Ions Atom that has gained or lost an electron. Protons are never shared. Gain or loss of an electron changes the charge of the atom.

17. Ions An ion with a negative charge is an anion. Nomenclature – Part of the name and –ide – Chloride

18. Ions An ion with a positive charge is a cation. Nomenclature – Use the elemental name – sodium

19. Table Salt Ionic Compound name – Sodium Chloride

20. Formation of Ionic Bonds Chemical bond- force that holds atoms or ions together. Ionic Bond- force that holds cations and anions together (charges and electron transfer)

21. Ionic Compounds Chemical formula- notation that shows what elements a compound contains and the ratio of the atoms or ions of the elements in the compounds. Ratio-relationship between 2 numbers. NaCl – One sodium ion for every chloride ion.

22. Ionic Compounds MgCl₂ One magnesium atom must share two electrons with two chlorine atoms. One magnesium ion for 2 chloride ions.

23. Crystal Lattices

24. Crystal Lattice Lattice- orderly design. Ionic compounds are arranged in specific ways. The shape of the compound helps reveal information about ion arrangement.

25. Properties of Ionic Compounds The properties of an ionic compound can be explained by the strong attractions among ions within a crystal lattice. High melting point Good conductor when melted Result of 2 factors: – Attraction – Kinetic energy of particles

26. Covalent Bonding Covalent Bonds Unequal Sharing of Electrons Attraction Between Molecules

27. Covalent Bonds Sharing Electrons Molecules of Elements Multiple Covalent Bonds

28. Sharing Electrons A covalent bond is a chemical bond in which two atoms SHARE a pair of valence electrons. When two atoms share one pair of electrons, the bond is called a single bond.

29. Molecules of Elements A molecule is a neutral group of atoms that are joined together by one or more covalent bonds. Attractions between shared electrons and the protons in each nucleus hold the atoms together in a covalent bond.

30. Multiple Covalent Bonds Example: Nitrogen – Chemical formula N₂

31. Unequal Sharing of Electrons Polar Covalent Bonds Polar and Nonpolar Molecules

33. Unequal Sharing of Electrons Periodic Table Trends: – Elements to the right (except for noble gases) have a greater attraction for electrons. – Elements at the top of a group have a greater attraction for electrons.

35. Polar Covalent Bonds Compound molecules may not share electrons equally. The atom with the greater attraction for electrons has a partial negative charge. The other atom has a partial negative charge.

36. Polar Covalent Bonds Example: HCl – Chlorine has a greater attraction for the electron than the hydrogen does.

37. Polar and Nonpolar Molecules The type of molecule and its shape are factors that determine whether a molecule is polar or nonpolar.

39. Attractions Between Molecules Attractions between polar molecules are stronger than attractions between non-polar molecules.

40. Naming Compounds and Writing Formulas Describing Ionic Compounds Describing Molecular Compounds

41. Describing Ionic Compounds Scientists are obsessed with classification… Naming compounds helps engineers differentiate between what compounds they are using.

42. Describing Ionic Compounds Binary Ionic Compounds Metals with Multiple Ions

44. Describing Ionic Compounds The name must distinguish the compound from other ionic compounds containing the same elements. The formula must describe the ratio of the ions in the compound???????