1. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2

2. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C Elements & Ions Notes

3. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 What is an atom made up of? - - + + + -

4. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Let’s review The top number is the atomic – the number of - - + + + - 3 Li 6.941 PROTONS number The bottom number is the average atomic - the number of mass protons & neutrons In a neutral atom, there are the same number of electrons as protons

5. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Lets Practice N Give the number of e -, p + and n for each examples C Mg

6. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Ok.. Now do you remember Bohr’s models? Lets try to practice drawing the Bohr’s model with the last 3 examples?

7. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 + + + - + + + - - - - - - - - - - - - - - - - - - + + + + + + + + + + + + + + - - - - Ca.. This is a Bohr Model of a Calcium atom Since only the outer shell, or valence electrons are involved in bonding, a simpler diagram is used called a Lewis Dot or e-dot Diagram Lewis Dot or e- diagram

8. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 How do I determine the number of valence electrons instead of drawing out the Bohr’s model every time? Write down your hypothesis on the note taking guide

9. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 108765 2 943 1 Valence electrons are….. # of protons = atomic number # of valence electrons = group or family number in the representative or A elements 1 7 4 5 6 2 3 1 1A 2 2A 3 3B 4 4B 5 5B 6 6B 7 7B 11 1B 12 2B 13 3A 14 4A 15 5A 16 6A 17 7A 18 8A 8 9 10 8B

10. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Let’s Practice…. Give the # of valence electrons of the following elements Na SiS Group #: 146 # of valence e- e- : 1 4 6

11. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Your Turn: Give the # of Valence e for each of the following elements. Mg B C Ne N O F

12. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 How do I draw a Lewis or e-dot diagram? Step 1: Write down the symbol of the element. Note: the symbol of the element represents the nucleus of the atom and inner most electrons or Core electrons. Step 2: Determine the number of valence electrons each element has. Step 3: Place one dot for each electron present in the last energy level. Step 4: Draw single dots on each side of the element before pairing them.

13. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Let’s Practice Hydrogen’s Bohr Model Now it’s Lewis dot structure…. H

14. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Your Turn… Give the e-dot diagrams for the following elements: Mg B C Ne N O F

15. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Is this element stable? Stable atoms: atoms with 8 valence electrons.Stable atoms: atoms with 8 valence electrons. –Ex: Neon, a group 8 also called the noble gases, atom has 8 valence electrons. Unstable atom: Atoms with only a few valence electronsUnstable atom: Atoms with only a few valence electrons Octet Rule: Atoms wanting or needing to get 8 valence electrons to become stable.Octet Rule: Atoms wanting or needing to get 8 valence electrons to become stable. - - + + + - -

16. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 1 1A 2 2A 3 3B 4 4B 5 5B 6 6B 7 7B 11 1B 12 2B 13 3A 14 4A 15 5A 16 6A 17 7A 18 8A 8 9 10 8B Atoms are stable when there are 8 valence electrons.Atoms are stable when there are 8 valence electrons. Atoms with only one or seven valence electrons are especially reactive.Atoms with only one or seven valence electrons are especially reactive. these electrons are available to be “shared” or “stolen” by other atomsthese electrons are available to be “shared” or “stolen” by other atoms

17. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Why do atoms combine? Atoms of elements want to fill their valence shells to become stable so they share or steal electrons. Sometimes…. positive charged ions are attracted to negatively charged ions and they will combine. The attraction between atoms is the glue (a chemical bond). The bonded atoms are now a compound.

18. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 What are compounds? Think about a compound word such as hotdog….. The words hot and dog have defined meanings or properties. The combined word has a new meaning.

19. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Compounds are chemically bonded atoms.Compounds are chemically bonded atoms. What are compounds? Chlorine (Cl) is a toxic, yellowish gas.Chlorine (Cl) is a toxic, yellowish gas. The properties of compounds are different than the properties of uncombined atoms.The properties of compounds are different than the properties of uncombined atoms. For example, sodium (Na) is a soft, shiny metal that reacts violently with water.For example, sodium (Na) is a soft, shiny metal that reacts violently with water. When combined, NaCl is table salt.When combined, NaCl is table salt. +=

20. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Sometimes, electrons are transferred between atoms. Sometimes, electrons are transferred between atoms. Ionic Compounds What will happen to a positive substance & a negative one? What will happen to a positive substance & a negative one? If an atom gains an electron, what will its charge be? What if another atom loses an electron? If an atom gains an electron, what will its charge be? What if another atom loses an electron? Click here to see an animation of an ionic bond!

21. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 13 3A Ionic bonds occur between metals and non-metals on the periodic table. Ionic Compounds In general, the metallic elements in groups 1, 2, and 13 have positive valence numbers. This means they have electrons to give up. 1 1A 2 2A 3 3B 4 4B 5 5B 6 6B 7 7B 11 1B 12 2B +3 14 4A 15 5A 16 6A 17 7A 18 8A 8 9 10 8B The non-metallic elements in groups 5, 6, and 7 have negative valence numbers. This means they are anxious to steal electrons. +1 +2 -2-3 What is the relationship between the charges and the magic number 8? Think about the charge of electrons… Why might 4A (14) & 8A (18) have no charges listed?

22. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Review….Atoms Neutral charge same # protons (+) & electrons (-)

23. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Review….. Ions Charged atoms Gained or lost electrons Protons are never changed Can also be the same # as the oxidation numbers

24. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Ionic Compounds Composed of (+) cation and (-) anion for a net charge of zero

25. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 What are Cations? A (+) charged ion = cation ion Properties: Metals (located on the left side of the periodic table and below the zig zag line) They give away electrons Ions formed from groups 1A, 2A, 3A, etc where they have 1, 2, 3, and etc. valence electrons

26. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 What are Anions? A (-) charged ion = anion Properties: Nonmetals (located on the right side of the periodic table and above the zig zag line) They steal or take electrons Ions formed from groups 7A, 6A, 5A, etc where they have 7, 6, 5, and etc. valence electrons

27. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Charges? Cont… Cations: Group 1 A = +1 Group 2A = +2 Group 3A (metals (below the zig-zag line)) = +3 Group 4A (metals (below the zig-zag line)) = +4 Group 5A (metals (below the zig-zag line))= +5 Group 6A (metal (below the zig-zag line)) = +6

28. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Charges? Cont… Anions: Group 8A = 0 (noble gasses) Group 7A = -1 Group 6A = -2 Group 5A (non metals (above the zig-zag line)) = -3 Group 4A (non metals (below the zig-zag line)) = -4 Group 3A (non metals (below the zig-zag line)) = -5

29. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 What about the other elements on the Periodic Table? They are called the Transition elements. Charges are ?… –Most have Two or more charges each –Listed on the periodic table or given to you –Given by roman numerals

30. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 How do you illustrate Ionic Compounds? Draw the dot diagrams for the 2 elements. What about a Na & a Cl?.... Cl... Na. What does each ion want?

31. H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C H2CH2C CH 2 Practice Give the Lewis dot diagrams for the following combination of elements. #1: K & I #2: Rb & S #3: Be & O #4: Al & Cl