Unit 3 Do Now READ pp. 210-211 (Some claims made may not be valid) Answer the following questions: What do you like about the commercial What do you not like about the commercial What would your commercial look like? 1. SWBAT answer short answer and multiple choice questions on 2.D. 2. SWBAT identify the objectives and requirements for the unit 3 project. 3. SWBAT identify petroleum based projects and hypothesize what life would be like without petroleum. You will learn about: Molecules that make up petroleum Uses as fuels & product building blocks Learning will help you analyze the claims Teams will design & present advertisements featuring an imaginary, but plausible, vehicle that uses a particular type of fuel Biodiesel Compressed natural gas Hybrid gasoline-electric Hydrogen-oxygen fuel cell Other A. Petroleum: What is It? Refining of & uses for petroleum Electrons & covalent bonding in hydr0carbons Representations of & formula for hydrocarbons Intermolecular forces & properties of hydrocarbons pp. 212-236 What is petroleum? What material is it mined from? What two elements is petroleum made from? 1. SWBAT describe the chemical makeup of petroleum and how its refined.2. SWBAT describe and give examples of uses for petroleum.3. SWBAT explain hydrocarbon combustion reaction.4. SWBAT apply the location of petroleum to business, politics, and economy. Let’s make a list of the following items on the teacher’s desk: 1. SWBAT describe the chemical makeup of petroleum and how its refined. 2. SWBAT describe and give examples of uses for petroleum. 3. SWBAT explain hydrocarbon combustion reaction. 4. SWBAT apply the location of petroleum to business, politics, and economy. Let’s make a list of the following items on the teacher’s desk: Script for car ad highlighted energy & fuelrelated features that claimed to “help conserve petroleum resources” What properties make petroleum useful for burning & building? Focus on key compounds in petroleum Their physical properties, molecular structure, & how atoms bond to make these key compounds Crude oil – petroleum pumped from underground Mixture of many compounds Colorless to greenish-brown to black Fluid as water or as resistant to flow as soft tar. Crude oil is not useable Must be refined – separated into simpler mixtures Some mixtures are ready to use Others require more refining Refined petroleum is mainly a mixture of hydrocarbons, molecular compounds that contain only atoms of hydrogen (H) and carbon (C) Most petroleum is used as a fuel (89%) Burning petroleum provides nearly ½ of the total U.S. energy needs Gasoline powers millions of U.S. automobiles, each traveling 14,000 miles per year Other petroleum based fuels heat homes & office buildings, deliver energy to generate electricity, & power diesel engines & jet aircraft 1. What percent of petroleum is used for fuel? 2. What two elements is petroleum made from? 3. List two products that are made from petroleum. 4. What is petroleum mined from? Petroleum is also a raw material for many familiar & useful products New substances (e.g., medications & plastics) (7%) Other products (e.g., lubricants, road-paving tar) (4%) Nonrenewable resource What happens to the molecules contained in petroleum when they are burned or used in manufacturing? The atoms in them rearrange to form new molecules – as they do in all chemical reactions When hydrocarbons burn, the react with oxygen in the air to produce carbon dioxide and water – and, of course, energy CxHx + O2 CO2 + H2O + energy Methane burning CH4 + 2O2 CO2 + 2H2O + energy Ethane burning C2H6 + 7O2 4CO2 + 6H2O + energy Petroleum is not uniformly distributed around the world 66% Middle Eastern Nations 5% North America 4% Central Asia, Far East, Oceana Figure 3.4, p. 214 – more details Answer the questions on worksheet 3.A.1. We will discuss answers as a class. How would the following might affect the long-term regional petroleum availability, use, and trade: 1. Industrialization/modernization of second and third world nations 2. Political unrest in the Middle East 3. Population growth in China and India 4. Depilation of Alaskan oil reserves 1. Which area of the world contains the most petroleum? 2. What area of the world uses the most petroleum? 3. What product of burning fossil fuels is a danger to our environment? 4. What is the goal of the combustion reaction? 1. SWBAT explain fractional distillation. 2. SWBAT draw and label a fractional distillation tower by temperature, intermolecular forces, and number of hydrocarbons. 3. SWBAT describe the relationship between alkanes and their boiling points. pp. 215-218 – Investigating Matter Separation of liquid substances based on their different boiling points Distillate: Condensed liquid collected Crude oil is a mixture of many compounds It takes more than simple distillation to separate them Refining process separates the crude oil mixture into several smaller mixtures, called fractions This process is called fractional distillation Compounds in each fraction have a particular range of boiling points & specific uses Refining Crude Oil These fractionating towers contain many different levels of condensers to cool the oil vapor as it rises. Temperatures range from about 400oC (at the base) to 40oC (at the top). Crude oil is heated to about 400oC in a furnace Pumped into the base of a distilling column (fractionating tower), which is usually more than 100 ft (30 m) tall Many components of the heated crude oil vaporize Temperature of the distilling column is highest at the bottom Temperature drops towards the top Trays arranged at appropriate heights inside the column collect the various condensed fractions Smaller, lighter molecules – lowest boiling points – either condense high in the column or are drawn off the top of the tower as gases Fractions with larger molecules & higher boiling points are more difficult to separate Require more heat energy to vaporize Condense back into a liquid in trays lower in the column Substances with the highest boiling points never vaporize Thick (viscous) liquids, called bottoms, drain from the column’s base pp. 219-220 1. Petroleum’s gaseous fraction compounds with low boiling points (less than 40oC) small hydrocarbon molecules: 1-4 carbons Low intermolecular forces (forces of attraction) LESS INTERMOLECULAR FORCES: Easily separate & rise 2. Petroleum’s liquid fraction – varied boiling points (less than 40oC – 370oC) 5-20 carbons higher intermolecular forces 3. Petroleum’s greasy fraction – viscous bottoms boiling points (over 370oC) Over 20 carbons highest intermolecular forces Solids at room temperature Draw a fractioning tower: Label the following: Gasoline Gases High temperature/Low temperature Viscous substances Crude oil Heat source Short hydrocarbons/ Long hydrocarbons Strong intermolecular forces/Weak intermolecular forces p. 220, Developing Skills LAB! Label the following picture: Diesel Gasoline Heat Source Residue Crude Oil Gas 1. SWBAT review fractional distillation. 2. SWBAT define covalent bonding. 3. SWBAT draw Lewis dot structures for several elements. pp. 220-224 Organic Chemistry – focuses on hydrocarbons & substances that are made from them Called “organic”, because early chemists that living systems were needed to produce hydrocarbons Not so – for 150 years - reactants other than petroleum have been used to make “organic” compounds Hydrocarbon molecules Carbon atoms join to make a carbon chain backbone Hydrogen atoms are attached to the carbon chain backbone Carbon’s ability to bond the way it does explains the abundance of different hydrocarbon compounds What holds atoms together? Answer is related to the arrangement of electrons in atoms. Atoms Nucleus Protons Neutrons Shells (Energy Levels) Electrons Each shell can hold a specific maximum number of electrons Refer to Periodic Table H 1e- in 1st shell He 2e- in 1st shell 1st shell only holds 2e-, so new shell starts Li 3e- - 2 in 1st shell, 1 in 2nd shell Be 4e- - 2 in 1st shell, 2 in 2nd shell B 5e- - 2 in 1st shell, 3 in 2nd shell C 6e- - 2 in 1st shell, 4 in 2nd shell N 7e- - 2 in 1st shell, 5 in 2nd shell O 8e- - 2 in 1st shell, 6 in 2nd shell F 9e- - 2 in 1st shell, 7 in 2nd shell Ne 10e- - 2 in 1st shell, 8 in 2nd shell 2nd shell only holds 8e-, so new shell starts Atoms whose last (outer) shell is filled are unreactive Found on the right side of the Periodic Table – Group 18 They all have 8 e- in the outer shell (except for He, because the 1st shell can only hold 2e-) Called the “noble gases” or “inert gases” Atoms in Group 17 are very reactive They tend to gain 1e- to finish the shell Example: F + 1e- F1- (8e- in outer shell) Atoms in Group 1 are very reactive They tend to lose 1e-. In the process, they lose the entire outer shell. The shell that is now exposed is filled, or finished. Example: Na Na1+ + 1e- (8e- in outer shell) Compounds made of nonmetals achieve filled outer shells by sharing electrons Covalent bonding H has 1e- in a shell that can hold 2e-. So, it is “missing” 1eIf two H atoms come together, they can each share the 1e- they have. Each H has the use of its e- as well as the use of the e- from the other H. H + H H:H Single covalent bond – 1 shared pair of e- C atom has 6e-, 2 in the 1st shell & 4 in the 2nd 2nd shell needs 4 more e- to have a total of 8eMethane, CH4, is the simplest hydrocarbon What would the “dot” equation look like? 4 single bonds Structures showing the valence e- as dots are called: Electron-dot formulas Lewis dot structures Lewis structures For convenience, each e- pair can be written as a dash. These kind of representations are called a structural formulas. These are all 2-dimensional representations of molecules 3-dimensional models give a more accurate representation Help predict a molecule’s physical & chemical behavior In 3A.7, you will build models of alkanes Each carbon in an alkane forms 4 single covalent bonds with other atoms Draw the Lewis Dot Structure for: 1. C 2. H 3. N 4. Br 1. SWBAT define covalent bonding. 2. SWBAT draw Lewis dot structures for several elements. 3. SWBAT draw the Lewis dot structure and structural formula for several different molecules. Rule 1: Add together the number of valence electrons for each atom. Rule 2: Write out the elements without their electrons. Rule 3: Add electrons around the elements. Rule 4: Check to make sure EACH element has a filled valence shell. Rule 5: Count the number of electrons around each element and compare it to step 1. They should have the same number. 1. C2H6 DO NOW Draw the lewis dot and structural formula for propanol. C3H7OH 1. SWBAT build and describe ball and stick models of isomers. 2. SWBAT differentiate among straight carbon, branched carbon, and ring structures. 3. SWBAT determine the IUPAC name for alkanes and draw out molecules. Alkanes: hydrocarbons with single bonds Alkenes: hydrocarbons with one or more double bonds Alkynes: carbons with one or more triple bond Straight-Chain Alkanes: Carbons in a straight line Branched-Chain Alkanes: One carbons can be linked to 3 or 4 other carbons Ring Structure Alkanes Form a circle of carbons Structural Isomer: Molecules that have the same molecular formula but different arrangements of atoms. Structural Isomers of Propanol Meth Eth Prop But Pent Hex Hept Oct Non Dec 1 2 3 4 5 6 7 8 9 10 Worksheet Supplement 3.A.9 pp. 224-228, Investigating Matter 1. CH3-CH2-CH2-CH2-CH3 2. CH3-CH-CH2-CH I CH3 3. 4. 1. SWBAT graph alkanes and determine the best fit line through the data. 2. SWBAT answer questions analyzing the data points. Tetrahedron: 3D shape similar to a pyramid Condensed Formula: CH3-CH2-CH2-CH3 Write out all the carbons Molecular Formula: C4H10 CnH(n+2) Each type of atom is written only once Turn to page 228. Graph the data on page 226 Answer questions #1-3 on page 229 What did you notice about the number of carbons and boiling points of alkanes? Why do you think this happens? 1. SWBAT draw models of isomers. 2. SWBAT draw a conclusion about branched vs. straight chain isomers and boiling points. 3. SWBAT hypothesize about how climate affects molecules in different fuels. Drawing structural isomers Draw 2 isomers of butane: Try to come up with an many as possible structural isomers for hexane. Turn to page 231 and with a partner answer questions #1-3 http://www.whfreeman.com/ChemCom/ The more branches the LOWER the boiling point. WHY? The more compact, spherical shape of the branched isomer affords fewer contacts. (Easier to separate). Less Surface Area Pg. 235 #29-31, 33, 34, 37, 38 Draw the lewis dot structure and structural formula for the following molecules: 1. CF4 2. H2O 3. NH3 1. SWBAT answer multiple choice and matching questions in a jeopardy game to review for their test on Thursday. Using the worksheet, list: 1. your name 2. 2 things your understand 3. 2 things you want to review next class. 1. The yne suffix (ending) indicates an alkyne or ene suffix indicates an alkene. 2. Select the longest chain containing the double or triple bond. 3. Number from the end nearest the double or triple bond. 4. Specify where the bond starts. EX. 1. 2. CH3-CH=CH-CH3 3. CH3-C CH CH3-C C-CH3