Have you ever heard the word bonding before?

2. If so, where did you hear it and what does it mean? Have you ever heard the word bonding before? If you have never heard it before write down what you think it means?

3. Bonding is what keeps elements and ions of compounds together!!!

4. What’s the difference between an Element and a Compound?Give an example of each and explain why.

5. Elements An element is a substance that cannot be broken down into different substances. It is the smallest form of matter that has the same characteristics of that substance. Examples: Au (gold), Na (sodium) etc.

6. COMPOUNDS Define what a compound is? Two or more DIFFERENT atoms (elements) that are chemically bonded together because of a chemical reaction. We use chemical formulas to represent compounds. Can you think of any…? H2O (Wudder) CO2 (Carbon Dioxide) CH3COOH + NaHCO3 ===> CH3COONa + H2O + CO2

7. 1 2 3 D Mixture of Compounds AElement B Compounds 4 5 6 E Mix of Elements/ Compounds CMix of Elements A Elements

8. A New Language Let’s do the Vial Lab!

9. We will talk about4 TYPES OF BONDS IONIC COVALENT METALLIC HYDROGEN (Ions) (Sharing valence electrons) (Metals) (Ions)

10. IONIC BONDS • Form between ions with opposite charges: + and -. (a metal and a non-metal) • They bond because the opposite charges are attracted to each other. (Think magnets!!!)

11. IONIC BONDS Like charges repel each other! Ions and ionic bonds form because electrons are transferred from one atom to the other

12. Properties ofIONIC BONDS • Ionic compounds have high melting and boiling points. • These are very strong bonds. • An example is Na+1 + Cl-1 = NaCl (salt) NaCl Melting point 801 °C NaCl Boiling point1465 °C

13. IONIC BONDS Only certain ratios (combinations) of elements result in the formation of Ionic compounds. For ex: Lithium (Li) will react with Fluorine (F) to form LiF. BUT, it will NOT form LiF2, LiF3, etc. Magnesium (Mg) will react with Fluorine to form MgF2. BUT, it will NOT form MgF, MgF3, etc.

14. IONIC BONDS • When writing a chemical formula for an ionic compound: *The charges have to balance to create a neutral compound.*

15. IONIC BONDS • For example: - With salt the charges are both 1: Na+1 and Cl-1 So we just need one of each ion to make the compound neutral = the ratio is 1:1 = NaCl

16. IONIC BONDS • What if the charges are not the same number??? - Like Li+1 + O-2 Here you will not have a 1:1 ratio. You need to balance the chemical formula…

17. IONIC BONDS • What could you do to get the charges to cancel out if you wanted to form this ionic compound??? Li+1 + O-2 ANSWER: You would need to use 2 Li+1 for every O-2!!! = Li2O

18. 1.) K and N 2.) Ca and F 3.) Li and Cl 4.) Mg and Si 5.) Al and O 1.) K3N 2.) CaF2 3.) LiCl 4.) Mg2Si 5.) Al2O3 IONIC BONDSLet’s Practice!!! Write chemical formulas for:

19. How did you do??? 6.) Ca and Cl 7.) K and P 8.) Mg and Cl 9.) Li and P 10.) K and O 6.) CaCl2 7.) K3P 8.) MgCl2 9.) Li3P 10.) K2O IONIC BONDS

20. Chemical Formulas Rb and ClNa and S Li and P 1. Hints: The metal comes first, the non-metal comes second Change the end of the name of the second element to “ide” Copy down this table for your answers. 2. If you mix Calcium Chloride (CaCl2) into a glass of water until it dissolves, what is the chemical formula?

21. Chemical Formulas Rb and ClNa and S Li and P 1. Hints: The metal comes first, the non-metal comes second Change the end of the name of the second element to “ide” Rb +1 Cl -1 RbCl Rubidium Chloride Na +1 S -2 Na2S Sodium Sulfide Li +1 P -3 Li3P Lithium Phosphide 2. If you mix Calcium Chloride (CaCl2) into a glass of water until it dissolves, what is the chemical formula? CaCl2 (aq)

22. Ionic Bonds Warm-upWrite the chemical formulas for the compoundsformed when these ions bond: 11.) Al & S 12.) Rb & O 13.) Be & F 14.) Al & Cl 15.) Ca & N 16.) Ga & Se 11.) Al2S3 12.) Rb2O 13.) BeF2 14.) AlCl3 15.) Ca3N2 16.) Ga2Se3

23. Questions Without using your notes, answer the following questions. Write the questions! • What is a compound? Two or more DIFFERENT atoms (elements) that are chemically bonded together because of a chemical reaction. 2. Which formula is a compound and why? C8H10N4O2 or F2 C8H10N4O2= compound 3. What are the element(s) that make up each chemical formula in question 2? How many are in each element? 8 Carbon, 10 Hydrogen, 4 Nitrogen, 2 Oxygen 2 Fluorine

24. COVALENT BONDS • Form between two non-metals • They bond because the outer electron rings are not full so they share valence electrons! • (The atoms are NOT stable.)

25. Properties of COVALENT BONDS • Covalent compounds will have low melting and boiling points. • These are usually weak bonds. • Some examples are H2O (water/ wudder), and CO2 (Carbon Dioxide)

26. COVALENT BONDS • The reason H2O is covalent: Remember H can be a metal or a non-metal!!! (See RFA 11) Here H is behaving like a non-metal. Hydrogen is usually a non-metal!

27. Let’s Practice!Write the following compounds and determine if they are Ionic or Covalent? 1.) NH3 7.) AlCl3 2.) NaCl 8.) P2O5 3.) CH4 9.) Li3P 4.) CO2 10.) BN 5.) CaCl2 11.) N2O 6.) KBr 12.) MgS

28. 1.) NH3Covalent 2.) NaCl Ionic 3.) CH4Covalent 4.) CO2Covalent 5.) CaCl2Ionic 6.) KBr Ionic 7.) AlCl3 Ionic 8.) P2O5 Covalent 9.) Li3P Ionic 10.) BN Covalent 11.) N2O Covalent 12.) MgSIonic ANSWERS…

29. Lewis Structures Electron Dot Diagrams • We can show how the atoms share or transfer electrons by drawing electron dot diagrams. • You will only use the valence e- for dot diagrams.

30. Dot Diagrams • Start the dot diagram by writing the atomic symbol for the atom. Ex: Mg The symbol has 4 sides…

31. Dot Diagrams 2 Mg Each side can hold up to 2e- You cannot pair the electrons until there is one on each side. 1 3 4

32. Dot Diagrams 2 Mg Mg only has 2 valence e-. So it’s dot diagram looks like this: Mg Let’s try… Si how about… S 1 3 4

33. 1.) Cl 2.) Al 3.) Na 4.) Sn 5.) Ar Dot Diagrams Practice!!! Draw the Dot Diagrams for:

34. Dot Diagrams Now we can put individual diagrams together to show whether atoms transfer or share their valence e-!!! Who donates their electrons, metals or non-metals? Metals always donate their electrons!

35. Dot Diagrams for Ionic Bonds In an Ionic Bond, atoms are transferring their valence e- … To show this “transferring” , we draw arrows between the Atomic Symbols to represent the transferring of e-. We can show this w/ dot diagrams. For Ex: (Li + Cl = LiCl) Cl Li

36. Dot Diagram Practice for Ionic Bonds • BeO • NaCl • MgS • CaCl2 • LiP • AlCl

37. Dot Diagram Practice for Ionic Bonds 2. NaCl 3. MgS

38. Dot Diagram Practice for Ionic Bonds 5. LiP 6. AlCl

39. Dot Diagrams for Covalent Bonds In a Covalent Bond, atoms are sharing their valence e- … To show this “sharing”, we draw a BAR between the Atomic Symbols to represent the sharing of e-. One bar = 2 e-. For Ex: H2O

40. Dot Diagrams for Covalent Bonds One bar = 2 e-. For Ex: H2O (draw out the individual dot diagrams first.) H O H ***H’s ALWAYS have to go on the ENDS.

42. Dot Diagram Practice for Covalent Bonds • CO • CH • SO • NH • SiO • CF

44. Bonding Dot Diagram Steps 1.) Identify the type of bond you have. (Covalent or Ionic) 2.) Separate the individual elements and put them in a line. Put the atomic symbol w/ least amount of valance electrons in CENTER!!! 3.) Except the Hydrogen’s!!!! Remember H’s have to be on ENDS!!! 4.) Draw the “dots” for each atomic symbol.

45. Bonding Dot Diagram Steps 5.) Show either the transferring or sharing of e- with arrows or bars. 6.) If sharing (covalent bonds)…connect the “lonely” dots between DIFFERENT symbols!!! 7.) Count the e- around each atomic symbol to make sure there are 8!!! (ONLY 2 for H!)

46. 1234 HONC Based on your prior knowledge of atoms and their valance electrons, what in the world does 1234 HONC mean? Hydrogen, Oxygen, Nitrogen, Carbon Based on their valance electrons, how many atoms can bond to each of them? 1 2 3 4 H O N C H= can form one bond. O= can form two bonds. N= can form three bonds. C= can form four bonds. **This works for COVALENT bonds only**

47. 1.) NF3 2.) Sr3N2 Dot Diagram Practice

48. 1.) NF3 2.) Sr3N2 3.) Rb2O 4.) CH3Cl 5.) Al2S3 6.) Na3N Dot Diagram Practice

49. 3.) Rb2O 4.) CH3Cl Dot Diagram Practice

50. 5.) Al2S3 6.) Na3N Dot Diagram Practice