Unit 3

 READ pp  (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? Do Now

 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

 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.

Intro to 3.A. Petroleum  Let’s make a list of the following items on the teacher’s desk:

 Script for car ad highlighted energy & fuel- related 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?

PPetroleum is also a raw material for many familiar & useful products NNew substances (e.g., medications & plastics) (7%) OOther products (e.g., lubricants, road-paving tar) (4%) N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 C x H x + O 2  CO 2 + H 2 O + energy

Methane burning CH 4 + 2O 2  CO 2 + 2H 2 O + energy

Ethane burning C 2 H 6 + 7O 2  4CO 2 + 6H 2 O + 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 – Investigating Matter

 Separation of liquid substances based on their different boiling points  Distillate:  Condensed liquid collected

3A.3 Petroleum Refining  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 400 o C (at the base) to 40 o C (at the top).

3A.3 Petroleum Refining  Crude oil is heated to about 400 o C 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

3A.3 Petroleum Refining  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

3A.3 Petroleum Refining  Smaller, lighter molecules – lowest boiling points – either condense high in the column or are drawn off the top of the tower as gases

3A.3 Petroleum Refining  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

3A.3 Petroleum Refining  Substances with the highest boiling points never vaporize  Thick (viscous) liquids, called bottoms, drain from the column’s base

Refer to Figure 3.9, p. 219

3A.4 Examining Petroleum’s Molecules pp

3A.4 Examining Petroleum’s Molecules  1. Petroleum’s gaseous fraction  compounds with low boiling points (less than 40 o C)  small hydrocarbon molecules: 1-4 carbons  Low intermolecular forces (forces of attraction)  LESS INTERMOLECULAR FORCES: Easily separate & rise

3A.4 Examining Petroleum’s Molecules  2. Petroleum’s liquid fraction – varied  boiling points (less than 40 o C – 370 o C)  5-20 carbons  higher intermolecular forces

3A.4 Examining Petroleum’s Molecules  3. Petroleum’s greasy fraction – viscous bottoms  boiling points (over 370 o C)  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

3A.5 Hydrocarbon Boiling Points 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.

3A.6 Chemical Bonding pp

3A.6 Chemical Bonding  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

3A.6 Chemical Bonding  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

Hydrocarbon Chains

3A.6 Chemical Bonding WWhat holds atoms together? A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

3A.6 Chemical Bonding Refer to Periodic Table  H 1e - in 1 st shell  He 2e - in 1 st shell  1 st shell only holds 2e -, so new shell starts

 Li 3e in 1 st shell, 1 in 2 nd shell  Be 4e in 1 st shell, 2 in 2 nd shell  B 5e in 1 st shell, 3 in 2 nd shell  C 6e in 1 st shell, 4 in 2 nd shell  N 7e in 1 st shell, 5 in 2 nd shell  O 8e in 1 st shell, 6 in 2 nd shell  F 9e in 1 st shell, 7 in 2 nd shell  Ne 10e in 1 st shell, 8 in 2 nd shell  2 nd shell only holds 8e -, so new shell starts

3A.6 Chemical Bonding

 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 1 st shell can only hold 2e - )  Called the “noble gases” or “inert gases”

3A.6 Chemical Bonding  Atoms in Group 17 are very reactive  They tend to gain 1e - to finish the shell  Example: F + 1e -  F 1- (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  Na e - (8e - in outer shell)

3A.6 Chemical Bonding  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” 1e -  If 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.

3A.6 Chemical Bonding H  +  H  H:H  Single covalent bond – 1 shared pair of e -

3A.6 Chemical Bonding  C atom has 6e -, 2 in the 1 st shell & 4 in the 2 nd  2 nd shell needs 4 more e - to have a total of 8e -  Methane, CH 4, is the simplest hydrocarbon  What would the “dot” equation look like?  4 single bonds

3A.6 Chemical Bonding  Structures showing the valence e- as dots are called:  Electron-dot formulas  Lewis dot structures  Lewis structures

3A.6 Chemical Bonding  For convenience, each e - pair can be written as a dash. These kind of representations are called a structural formulas.

3A.6 Chemical Bonding  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. C 2 H 6

 DO NOW  Draw the lewis dot and structural formula for propanol.  C 3 H 7 OH

 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

Meth1 Eth2 Prop3 But4 Pent5 Hex6 Hept7 Oct8 Non9 Dec10

 Worksheet Supplement 3.A.9

3A.7 Modeling Alkanes pp , Investigating Matter

 1. CH3-CH2-CH2-CH2-CH3  2. CH3-CH-CH2-CH I CH

 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:  CH 3 -CH 2 -CH 2 -CH 3  Write out all the carbons  Molecular Formula:  C 4 H 10  C n H (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

  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. CF 4  2. H 2 O  3. NH 3

 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