Write 10 Video Question. VSEPR Theory Practice Problems: VSEPR Theory: Common Mistakes: Lewis Diagrams Made Easy: How to Draw Lewis Dot Structures:

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1 Final Exam Extra Credit Checklist NOTE: ALL aspects of this exam review must be completed in order to earn +5 points toward your overall exam grade. The Final Exam Review is due the class period, the day of the final exam. We will be in the library May 14-May 17 using the computer lab in order to prepare for the final exam. Finish the data table & post-lab questions: Molecular Models Use the model kits and/or the online software to finish the following: Draw the Lewis Dot Structure Draw the Structural Formula Draw the Molecular Model (Use color, this will help to determine polarity) Identify the molecular shape Identify the molecule as either polar or nonpolar Finish the Post-Lab Questions Chapter 8: Covalent Bonding Go to and choose Final Exam EC tab to watch the links below. VSEPR Theory: Introduction: Write 10 Video Questions VSEPR Theory Practice Problems: Write 10 Video Questions VSEPR Theory: Common Mistakes: Write 10 Video Questions Lewis Diagrams Made Easy: How to Draw Lewis Dot Structures: Write 10 Video Questions Polar and NonPolar Covalent Molecules, Polar vs. Nonpolar CLEAR & SIMPLE: Write 10 Video Question Chapter 16: Solutions Go to and choose Final Exam EC tab to watch the links below. Molarity: Write 10 video questions from the video. Create 5 Molarity questions & answer key Mass/mass%: Write 10 video questions from the video. Create 5 Mass/Mass% questions & answer key Mole Fraction: Write 10 video questions from the video. Create 5 Mole Fraction Q s & answer key Mole fraction from Mass/mass%: Write 10 video questions from the video. Create 5 Mole Fraction from Mass/mass % & answer key Molarity From Mass/Mass%: Write 10 video questions from the video. Create 5 Molarity from Mass/Mass% questions & answer key Chapter 19: Acids, Bases & Titrations Go to and choose Final Exam EC tab to watch the links below. Acids, Bases, and ph: Write 10 video questions from the video. Solving ph, poh, H3O and OH: Write 10 video questions from the video. Create 5 Solving ph, poh, H3o & OH questions & answer key Acid-Base Equilibrium: Write 10 video questions from the video. Acid-Base Titration: Write 10 video questions from the video. Dilution Problems Chemistry Tutorial: Write 10 video questions from the video. Create 5 Dilution questions & answer key The Science of Fireworks Go to and choose Final Exam EC tab to watch the links below. Watch the video and write 10 complete sentences describing what the lecture is discussing and how it relates to what you have learned during the school year regarding concentration, reaction chemistry, balanced equations, mole ratios, etc.

2 Chapter 8: Covalent Bonding Finish the data table & post-lab questions: Molecular Models, NOTE checklist above!!! If you are not using the kits but using the computer lab, utilize the software programs below. Build A Molecule: 1. Use the Build A Molecule Java software that is already downloaded on the computer. 2. Double click the Finder file. 3. Open the Applications Folder and look for build-a-molecule_en.jnlp it looks like a cup of coffee. 4. Double Click to open. 5. You will encounter prompts to update Java..click Later. 6. If it prompts you for another update click Remind Me Later. 7. Then choose Run. 8. If the Build A Molecule Java software is NOT already on the computer, go to the following website: Molecular Shapes: 1. Go to PHET. Choose Chemistry. 3. The choices are in alphabetical order, find Molecular Shapes. 4. Double click on the program. 5. Choose Model. 6. Make sure you check Molecular Geometry located at the bottom left of the screen.

3 Molecular Models & Shapes of Molecules Purpose: Build molecules using molecular model kits. Draw Lewis dot structures and Structural Formulas for each of these molecule. * Determine the Geometry around the central atom, the number and types of bonds, and polarity of the molecule. Pre-Lab Notes: The attraction between two atoms in a molecule is called a chemical bond, specifically, a covalent bond. A Lewis Structure is a representation of covalent molecules where all the valence electrons are shown distributed about the bonded atoms as either: shared electron pairs (bond pairs) unshared electron pairs (lone pairs). A shared pair of electrons is represented as a short line (a single bond). Sometimes atoms can share two pairs of electrons, represented by two short lines (a double bond). Atoms can even share three pairs of electrons, represented by three short lines (a triple bond). Pairs of dots are used to represent lone pair electrons. Examples are shown for the molecules SF2 and CH2O below: Valence electrons are the electrons farthest from the nucleus and occupy the highest s and p orbitals. The number of valence electrons are the same as the group number located at the top of each group column. In this experiment you will draw the structural formula and electron dot formula (Lewis Dot Structure) and build and draw a model which will be constructed from spherical balls and connectors, where each ball represents an atom. The holes in ball represents the electrons and the connectors represent a bond.

4 Part I Procedure: Building Molecular Models: 1. When constructing a model, a hole in ball represents an electron that is necessary to complete an octet or duet (note there are atoms that need 4 or 6 total electrons specifically Group II and Group III, as opposed to 8 or 2, in order to fulfill complete pairs of valence electrons ). 2. Bonding electrons: Connect ball with connectors to represent bonds. Note the following: One rigid connector = single bond (one electron pair) Two flexible connectors = double bond (two electron pairs) Three flexible connectors = triple bond (three electron pairs) 3. Non-bonding electrons: Each unshared pair of electrons, known as a lone pair will be represented by 1 rigid connector with no ball at the other end of it NOTE: Our kits will not have holes for non-bonding domains, also known as unshared pairs. Thus, you will need to note your drawn Lewis Dot Structure in order to indicate the region(s) of lone pairs. 4. A molecular model uses different color balls to represent hydrogen, carbon, oxygen, chlorine, bromine, iodine, and nitrogen atoms. The color code for each ball is as follows: White/yellow = hydrogen (one hole) Black ball = carbon (four holes) Red ball = oxygen (two holes PLUS 2 lone pairs) Green ball = chlorine (one hole PLUS 3 lone pairs) Orange ball = bromine (one hole PLUS 3 lone pairs) Purple ball = iodine (one hole PLUS 3 lone pairs) Blue ball = nitrogen (three holes PLUS 1 lone pair) NOTE: if the blue nitrogen has more than three holes place tape to fill the additional holes. 5. To construct models: Add up the total number of valence electrons for the molecule, example H 2O: H: 2 (1 val. Electron) = 2 valence electrons O: 1 (6 val. Electrons) = 6 valence electrons Total val. Electrons = 8 Determine the central atom. This will the single atom in the formula, in this case oxygen. Place electron dots around the central atom to ensure that it follows the octet rule and then place the remainder of the atoms around the central atom and ensure that that follow the octet or duet rule. Lewis Dot Diagram Drawn Molecule (USE COLOR) Structural Formula 6. Build the molecule, using directions Draw the ball and stick model USE COLOR. Fill in the element symbol in the circles. 8. Draw the structural formula.

5 Formula Lewis Dot Structure (Include Total Electrons) Structural Formula Drawn Molecule Molecular Shape Polar Covalent NON- Polar Covalent Br 2 Liquid Bromine H 2O Water NF 3 Nitrogen Trifluoride CCl 4 Carbon Tetrachloride H 2S Dihydrogen Monosulfide N 2 Nitrogen Gas (Hint: triple bond) O 2 Oxygen Gas (Hint: double bond) CO 2 Carbon Dioxide (Hint: carbon is the central atom double bonds) HCN Hydrocyanic Acid Hint: place C as the central atom H 2CO Aldehyde Hint: place C as the central atom CH 3NH 2 Amine Hint: place C and N bonded together as central atoms

6 Formula Lewis Dot Structure (Include Total Electrons) Structural Formula Drawn Molecule Molecular Shape Polar Covalent NON-Polar Covalent I 2 Solid Iodine HOCl Bleach Water (Hint: Place oxygen as the central atom) H 2O 2 Hydrogen Peroxide (Hint: Place oxygens as the central atoms) N 2H 4 Hydrazine (Hint: Place nitrogens as the central atoms0 NH 2OH Hydroxylamine (Hint: Place oxygen & nitrogen as the central atoms) HONO Nitrous Oxide (Hint: Double bond between nitrogen & oxygen) C 2H 3Cl Vinyl Chloride (Hint: double bond between carbons) C 3H 4 Propyne (Hint: one triple bond between 2 carbons) HCOOH Carboxylic Acid Hint: place C as the central atom & double bond between carbon & oxygen)

7 Post-Laboratory Questions: 1. In your own words define the following terms: Covalent bond: Double bond: Electron dot formula: Octet rule: Single bond: Structural formula: Triple bond: Valence electrons: 2. Refer to the periodic table in order to predict the number of valence electrons for each of the following: H = C = O = Cl = N = 3. What do each of the following represent in the molecular model kit? A white/yellow ball: A black ball: A Red ball: A blue ball: One rigid connector: Two flexible connectors: 4. Draw the structural formula and Lewis Dot structure for each of the following: Formula Drawn Molecule Structural Formula Lewis Structure IBr CH 3Cl Cl 2CO

8 When you draw a Lewis structure for a molecule on paper, you are making a two-dimensional representation of the atoms. In reality however, molecules are not flat they are three-dimensional. The true shape of a molecule is important because it determines many physical and chemical properties for the substance. Name the type of structure shown left: What does the solid line between the two element symbols represent? What subatomic particle (protons, neutrons, or electrons) make up these solid lines? What does a pair of dots represent in the drawing of the molecules? What subatomic particle (protons, neutrons, or electrons) makes up each dot? Find the number of valence electrons (VE) for the following molecules. Draw the electron dot (Watch out for lone pairs!) The central atom is shown in bold.

9 Chapter 8: Covalent Bonding 1. VSEPR Theory: Introduction: 2. VSEPR Theory Practice Problems: 3. VSEPR Theory: Common Mistakes: 4. Lewis Diagrams Made Easy: How to Draw Lewis Dot Structures: 5. Polar and NonPolar Covalent Molecules, Polar vs. Nonpolar CLEAR & SIMPLE: Chapter 16: Solutions 1. Molarity: Create 5 Molarity questions and answer key. 2. Mass/mass%: Create 5 Mass/Mass% questions and answer key. 3. Mole Fraction: Create 5 Mole fraction questions and answer key. 4. Mole fraction from Mass/mass%: Create 5 Mole Fraction From Mass/Mass% questions and answer key. 5. Molarity From Mass/Mass%: Create 5 Molarity From Mass/Mass % questions and answer key.

10 Chapter 19: Acids, Bases & Titrations 1. Acids, Bases, and ph: 2. Solving ph, poh, H3O and OH: Create 5 Solving ph, poh, H3O & OH questions & answer key 3. Acid-Base Equilibrium: 4. Acid-Base Titration: 5. Dilution Problems Chemistry Tutorial: Create 5 Dilution questions & answer key The Science of Fireworks! Watch the video and write 10 complete sentences describing what the lecture is discussing and how it relates to what you have learned during the school year regarding concentration, reaction chemistry, balanced equations, mole ratios, etc.