WAY BACK WEDNESDAY! Catalyst – March “Perfect 10” in Name two differences between covalent and ionic compounds. 2. Danielle wants to see if using mouthwash will make her teeth whiter. Identify the IV, DV, and constants.

Today’s Objectives  SWBAT draw Lewis Dot Structures for covalent compounds with multiple covalent bonds.  SWBAT name covalent compounds.

Today’s Agenda  Catalyst  Multiple Covalent Bonds  Pause for Environmental Issues/Activist Letters…DHMO...Oh no!  Naming Covalent Compounds  Work Time Time  Exit Question

Multiple Covalent Bonds

LDS and Multiple Covalent Bonds Key Point #1: Sometimes atoms must share more than one pair of electrons in order to become stable.  This results in double and triple bonds.

Double and Triple Bonds  Double covalent bond: two pairs of shared electrons (four electrons)  Triple covalent bond: three pairs of shared electrons (six electrons) = =

Example: Oxygen  Two oxygen atoms show up at the Homecoming Dance. Each oxygen atom has $6, but it costs $8 per atom to go inside. The School of Elements is offering a discount for couples. It costs only $12 for a couple atoms to go inside. How can both atoms get inside if they each only have $6???  They can share…electrons that is!!!

Try this one: Nitrogen  Two nitrogen atoms show up at the Halloween Party. Each nitrogen atom has $5, but it costs $8 per atom to go inside. The School of Elements is offering a discount for couples. It costs only $10 for a couple atoms to go inside. How can both atoms get inside if they each only have $5???  Model the bond formation of this happy couple!

Steps for Multiple Bond LDS’s 1. Write formula 2. Number of valence electrons (ve-) 3. Number of octet electrons (oe-) 4. Number of bonds 5. Draw!

More Examples O 2 CO 2 CO COCl 2

Your Turn! CS 2 HCl NOBr

Practice Time! 1. C 2 Br 6 2. Se 2 3. SiSBr 2 4. Ge 2 H 4 5. OS 6. N 2

Strengths of Bonds  Triple  Double  Single Key Point #2: Bond strength increases with number of bonds. So….a double bond is stronger than a single bond, and a triple bond is stronger than a single or double bond.

The Environment…  In this class, I want you to learn the contents of basic chemistry…  However, I also want you to be able to understand the importance of chemistry in the environment.  There is a chemical, DHMO, that is especially ruining our environment in many ways… and something must be done.  You should have already letters to the government to help ban this awful, awful chemical

Surprise….  I have some DHMO with me today.  Does anyone want to see it??

Naming Covalent Compounds

Differences between ionic and covalent IONIC 2 ions come together! Metal + Nonmetal COVALENT No ions! Nonmetal + Nonmetal Examples: Na 1+ + O 2- CO 2

Naming Ionic and Covalent Compounds Key Poin t #3: When naming compounds, you must know which rules to use (ionic or covalent).  Ionic: Metal + Nonmetal  Covalent: Nonmetal + Nonmetal

Yo Yo! Let’s break it down! IONIC Metal + Nonmetal Writing Formulas: Kriss Kross charges Naming: 2 nd element ends in – ide, ignore subscripts COVALENT Nonmetal + Nonmetal Writing Formulas: Prefixes = subscript #s Naming: Use prefixes, 2 nd element ends in -ide

 A compound made from Lithium and Oxygen  How do we know if it is ionic or covalent?  Metals and non-metals make ionic compounds Naming Ionic Compounds

Ionic Bond  Ion: Li  Ion: O LiO

Ionic Bond  Ion: Li  Ion: O Li + O 2-

Ionic Bond  Ion: Li  Ion: O Li + O 2-

Ionic Bond  Cation: Li  Anion: O Li 2 O

Naming Ionic Compounds MgO

Naming Ionic Compounds MgO Magnesium Oxide

Naming Ionic Compounds CaCl 2

Naming Ionic Compounds CaCl 2 Calcium Chloride

Naming Ionic Compounds Al 2 O 3

Naming Ionic Compounds Al 2 O 3 Aluminum Oxide

Naming covalent compounds No Kriss Krossing!

Naming Covalent Compounds PCl 3

How do we know if this is a covalent compound?  Is it between a metal and a non-metal?  NO!!! Then, it is not ionic!!!  Is it between a non-metal and a non- metal?  YES!!! Then, it is covalent!

Naming Covalent Compounds Rule 1: If the first element has more than one atom, give it a prefix.

Naming Covalent Compounds 1 – mono-2 – di- 3 – tri-4 – tetra- 5 – penta-6 – hexa- 7 – hepta-8 – octa- 9 – nona-10 – deca-

Naming Covalent Compounds PCl 3

Naming Covalent Compounds PCl 3 Phosphorous

Naming Covalent Compounds Rule 2: The second element always gets a prefix, uses the root of the word and ends in - ide.

Naming Covalent Compounds PCl 3 Phosphorous

Naming Covalent Compounds PCl 3 Phosphorous Trichloride

Naming Covalent Compounds Rule 3: The “o” or “a” at the end of the prefix is dropped if the element begins in a vowel.

Naming Covalent Compounds N2ON2O

Rule 1: If the first element has more than one atom, give it a prefix.

Naming Covalent Compounds N 2 O Dinitrogen

Naming Covalent Compounds Rule 2: The second element always gets a prefix, uses the root of the word and ends in - ide.

Naming Covalent Compounds N 2 O Dinitrogen Monooxide

Naming Covalent Compounds Rule 3: The “o” or “a” at the end of the prefix is dropped if the element begins in a vowel.

Naming Covalent Compounds N 2 O Dinitrogen Monooxide

Naming Covalent Compounds N 2 O Dinitrogen Monoxide

Practice Time! EXAMPLES  CCl 4  As 2 O

Whiteboards SO

Sulfur Monoxide

NO 2

Nitrogen Dioxide

N2ON2O

Dinitrogen Monoxide

P2O5P2O5

Diphosphorous Pentoxide

CaCl 2

Calcium Chloride— It’s Ionic Suckas!!

PCl 5

Phosphorous Pentachloride

NF 3

Nitrogen Trifluoride

Independent Practice Time  Lucky you!

Write the names and formulas… First! Decide if it’s ionic or covalent! Write names 1. Na 2 O 2. CO 2 3. GeBr 4 4. Na 2 CO 3 5. Mg 3 P 2 6. K 2 S 7. N 2 S 3 Write formulas 1. Carbon monoxide 2. Barium nitrate 3. Xenon difluoride 4. Carbon tetrachloride 5. Sodium carbonate 6. Lithium fluoride 7. Nitrogen trifluoride

Exit Question 1. Write the formula for:  Silicon dioxide  Dihydrogen monoxide 2. Write the name for the following compounds:  CO 2  NH 3