Chemistry 30 Unit C Chemical Changes of Organic Compounds

CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 STUDENT NOTES AND EXAMPLES

Unit C is an introduction to organic chemistry. You will learn about common organic compounds and be able to describe their properties and reactions. You will also explore the significance of organic chemistry in technological applications and how they affect your quality of life. Knowledge and skills acquired in chemistry 20 Diversity and of matter and chemical bonding unit will be essential to success in this unit.

KEY CONCEPTS

 Organic compounds

 Naming of organic compounds

 Structural formulas

 Structural isomers

 Monomers and polymers

 Aliphatic and aromatic compounds

 Saturated and un-saturated hydrocarbons

 Identifying functional groups (alcohols, carboxylic acids, esters, and halogenated hydrocarbons)

 Organic reactions (addition, substitution, elimination, combustion, polymerization and esterification)

OUTCOME 1 – Explore organic compounds as a common form of matter

1. ____ define organic compounds as compounds containing carbon, recognizing inorganic exceptions such as carbonates, cyanides, carbides and oxides of carbon.

2. ____ identify and describe significant organic compounds in daily life, demonstrating generalized knowledge of their origins and applications; e.g., methane, methanol, ethane, ethanol, ethanoic acid, propane, benzene, octane, glucose, polyethylene.

3. ____ name and draw structural, condensed structural and line diagrams and formulas, using International Union of Pure and Applied Chemistry (IUPAC) nomenclature guidelines, for saturated and unsaturated aliphatic (including cyclic) and aromatic carbon compounds; a. containing up to 10 carbon atoms in the parent chain (e.g., pentane; 3-ethyl-2,4- dimethylpentane) or cyclic structure (e.g., cyclopentane) b. containing only one type of a functional group (with multiple bonds categorized as a functional group; e.g., pent-2-ene), including simple halogenated hydrocarbons (e.g., 2- chloropentane), alcohols (e.g., pentan-2-ol), carboxylic acids (e.g., pentanoic acid) and

1 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 esters (e.g., methyl pentanoate), and with multiple occurrences of the functional group limited to halogens (e.g., 2-bromo-1-chloropentane) and alcohols (e.g., pentane-2,3-diol)

4. ____ identify types of compounds from the hydroxyl, carboxyl, ester linkage and halogen functional groups, given the structural formula.

5. ____ define structural isomerism as compounds having the same empirical formulas, but with different structural formulas, and relate the structures to variations in the properties of the isomers.

6. ____ compare, both within a homologous series and among compounds with different functional groups, the boiling points and solubility of examples of aliphatics, aromatics, alcohols and carboxylic acids

7. ____ describe, in general terms, the physical, chemical and technological processes (fractional distillation and solvent extraction) used to separate organic compounds from natural mixtures or solutions; e.g., petroleum refining, bitumen recovery.

2 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017

Unit Assessment  Formative

Students must participate in lessons  - complete daily notes and examples.

Concept Checks  Complete daily activities and review new concepts regularly  Quizzes – 2  Labs – 1-2  Summative Unit Exam

3 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Lesson 1:

1) Define organic compounds as compounds containing carbon, recognizing inorganic exceptions such as carbonates, cyanides and carbides

2) Identify and describe significant organic compounds in daily life, demonstrating generalized knowledge of their origins and applications

STS: Demonstrate an understanding that science and technology are developed to meet societal needs and expand human capability

What is Organic Chemistry?

 The early definition related to compounds obtained only from ______.

 Today, it is a major branch of chemistry that deals with compounds of ______, called ORGANIC compounds*.

 *Carbon compounds that are ______and considered INORGANIC are compounds like:

 ______carbon monoxide (CO(g) ) and carbon dioxide (CO2(g) ), and

2- -  Ionic compounds of carbon-based ions, such as carbonate CO3 , cyanide CN , and carbide ions, SiC (silicon carbide)

 The major source of carbon compounds is still living or previously living things, such as plants, animals and all types of fossil fuels

4 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Formula Organic or Inorganic?

CaCO3(s)

C25H52(s)

Ca2C(s)

CCl4(l)

CH3COOH(l)

CO2(g)

KCN(s)

C12H22O11(s)

Organic or Inorganic??

Why is carbon special?

 There are millions or organic compounds and only a thousand inorganic compounds. WHY?

 Carbon has a ______of 4

 Remember Lewis Dot Diagrams from Chem 20??

 This means carbon can bond extensively and can bond together to form chains effectively = called ______

 Carbon covalently bonds by sharing 4 pairs of electrons. These bonds may be single, double or triple, all producing stable compounds

 Compounds can form with same number of each type of atom but different structures = ______

Determining Lewis Formulas

 So why do we care about ______?

 If we know how many bonding e-’s an atom has, we can predict what structure a molecular compound will have

5 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Atom Number of Number of Bonding Lewis Formula

valence e- bonding e- capacity

Carbon 4 4 4

Nitrogen

Oxygen

Halogens

Hydrogen

Polymers

 Examples of repeating carbon chains:

Isomers

 Compounds with the same number of each type of atom but different structures (C4H10)

 We will talk about this in more detail later

Importance of Organic Chemistry

6 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Building units of all living matter: carbohydrates, proteins, fats

 All foods are organic compounds

 Photosynthesis is a reaction that makes carbon a part of our food. Carbon is passed along through food chains and sugar from photosynthesis is modified and combined with other materials.

 Dead organisms are food for other organisms, or are buried in the earth and converted to fossil fuels like peat, coal and petroleum

 Petroleum is the source of fuel and starting material for plastics, fabrics and industrial chemicals

 The carbon cycle is an illustration of the interrelationship of all living things with the environment and with technologies that refine and use fossil fuels

 We will continually outline the importance of organic compounds in our daily lives

Carbon: The Element of Life VIDEO 20 minutes

Complete the worksheet provided as you watch the following video (20 min)

10 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Lesson 1 homework

 Ensure video worksheet is complete and in your notes to review later

 PG 47 Q 1, 4 & 5

 Extra Practice – LESSON 1

 What is coming up tomorrow?

 Naming alkanes, branched alkanes and cycloalkanes

11 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Lesson 2 : Section 9.2 (pg. 366-374)

1) Name and draw structural, condensed structural, and line diagrams and formulas for saturated and unsaturated aliphatic (including cyclic)

• Containing up to 10 carbon atoms in the parent chain/cyclic structure

• Containing only one type of a functional group or multiple bond

• Using the IUPAC nomenclature guidelines

2) Identify types of compounds from the functional groups, given the structural formula

3) Define structural isomerism and relate to variations in properties

Four Types of Formulas

1. Molecular Formulas C5H10(g)

**Not as useful for organic compounds because so many isomers can exist

2. Structural Formulas

3. Condensed Structural Formulas

4. Line Diagrams

– end of line segment represents carbon

– it is assumed to satisfy each carbon’s octet

12 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Naming Organic Compounds

 ______– contains only hydrogen and carbon atoms

 Straight line chains of carbon atoms

 Alicyclic hydrocarbons have carbon atoms forming a closed ring. Still considered aliphatic - ______

Alkanes Alkenes Alkynes

Naming Organic Compounds  In organic chemistry, names have a root and a suffix. The root describes the number of carbons present in the chain or ring. The suffix describes the type of compound it is.

Branches are like prefixes, using the root and –yl

Naming ALKANES

1. Find the parent chain. Use the appropriate root and suffix.

2. Number the carbon atoms, starting from the end closest to the branch(es) so that the numbers are the lowest possible

3. Name branches and their location number on the parent chain (us the suffix –yl for branches)

4. Write the complete IUPAC name, following the format: (number of location, if necessary) – (branch name) (parent chain)

NOW YOU TRY 

 If more than one of the same branch exist, use a multiplier to show this (di, tri). Remember to include all numbers

 Draw 2,4,6-trimethylheptane

 If different branches exist, name them in alphabetical order

ethyl before methyl (e before m in the alphabet)

17 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  If there is more than one branch of the same type, a locating number is given to each branch and a prefix indicating the number of that type of branch is attached to the name.

 This numbering prefix does not affect the alphabetical order of the branches

 Draw the structural formula for 3,4-dimethylhexane

Summary of Naming Alkanes

1. Find the parent chain. Use the appropriate root and suffix.

2. Number the parent chain carbon atoms, starting from the end closest to the branch(es) so that the numbers are the lowest possible

3. Identify any branches and their location number on the parent chain (us the suffix –yl for branches)

4. If more than one of the same branch exist, use a multiplier (di, tri) to show this. Remember to include all numbers

5. If different branches exist, name them in alphabetical order

6. Separate numbers from numbers using commas, and numbers from words using dashes (no extra spaces)

Don’t forget

 Questions will specifically ask about structural, condensed structural or line structural formulas.

 You must be comfortable drawing any of the three

Practice

 Write the IUPAC name for the following

Correct the following names: ** Draw and then re-name

 4-ethyl-2-methylpentane

 4,5-dimethylhexane

CYCLOALKANES

 Based on evidence, chemists believe that organic carbon compounds sometimes take the form of cyclic hydrocarbons:

 Cycloalkanes: Alkanes that form a closed ring

 General Formula CnH2n

 Two less hydrogens are present than in straight chain alkanes because the two ends of the molecule are joined

 Are these considered saturated?? Yes, because they have only single bonds and the max amount of hydrogen's bonded to the carbons

 Cyclo-compounds will have a higher boiling point than their straight chain partners (because there is an additional bond present)

Naming CYCLOALKANES

 Cycloalkanes are named by placing the prefix cyclo in front of the alkane name, as in cyclopropane and cyclobutane

 If branches are present, treat the cycloalkane as the parent chain and identify the branches.

 Since there is no end at which to start the numbering, use the lowest numbers possible

Name the following:

Lesson 2 homework

 PG 48 – 49 Q 6- 10

 Naming Alkenes, Alkynes, Cycloalkenes and Cycloalkynes

 Comparing properties of Isomers

22 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Naming Organic Compounds: Section 9.3 (pg. 374-380) Alkenes and Alkynes Lesson 3:

1) Name and draw structural, condensed structural, and line diagrams and formulas for saturated and unsaturated aliphatic (including cyclic

• Containing up to 10 carbon atoms in the parent chain/cyclic structure

• Containing only one type of a functional group or multiple bond

Structural Isomerism

 Compound with the same molecular formula but different structures

 They will have different chemical and physical properties – based on their different structures

 Find and name all of the isomers of pentane (C5H12(l))

Alkenes and Alkynes

 Alkenes – hydrocarbons containing a double C-C bond

 General formula (CnH2n) - (like cycloalkanes)

 Alkynes – hydrocarbons containing a triple C-C bond

 General formula (CnH2n-2) – (like cycloalkenes)

 Alkenes and Alkynes are considered unsaturated compounds. They do not have the maximum number of hydrogen atoms surrounding each carbon.

 Reactivity: Alkynes (highest), Alkenes, Alkanes (lowest)

Naming Alkenes and Alkynes

1. Find the parent chain. It MUST contain the multiple bond.

 If the bond is a double, the suffix for the parent chain will be -ene

 If the bond is a triple, the suffix for the parent chain will be –yne

2. Count carbon atoms so that the multiple bond will be on the lowest possible number. Indicate the number that the multiple bond falls on directly before the suffix

3. Name branches as before

 Draw the following as condensed structural formulas:

4-methylpent-2-yne

methylpropene

(why don’t we need a number?)

 Name the following:

4. It is possible for a molecule to have more than one double bond. These are called alkadienes and have the same

general formula as alkynes (CnH2n-2) If this is the case, indicate both numbers where the double bond is formed, and change the suffix to –diene. a) Draw buta-1,3-diene:

26 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 b) What is the IUPAC name for the following:

Cycloalkenes and –ynes

 The rules for naming cycloalkenes and cycloalkynes are the same as naming cycloalkanes

 The numbering for the carbon atoms begins with the double bond; the carbons of the double bond are carbons 1 and 2; lowest numbers possible

 Draw 3-methylcyclohexene

as a condensed structural formula

Lesson 3 homework

 PG 50-51 Q 1-6

 PG 52 Q 1-2

 Naming Aromatics

 Boiling point and Chemical Properties Analysis

Naming Organic Compounds: Aromatics

Lesson 4 : Section 9.4 (pg. 381-385)

1) Name and draw structural, condensed structural, and line diagrams and formulas for aromatic carbon compounds

Aromatics  Originally, organic compounds with an aroma or odour were called aromatic compounds

 Now, aromatics refer to compounds containing a ______

 Benzene’s formula is C6H6, which would suggest a highly unsaturated and reactive compound

 Benzene is actually quite ______and is considered more stable than alkenes and alkynes

 Did You Know?? Benzene is a carcinogen and is found naturally in petroleum – why would this be a problem?

 What do we know about benzene?

 Formula is C6H6 (3D link)

28 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Unreactive – so no true double or triple bonds

 Carbon-carbon bonds are the same length and strength

 Each carbon is bonded to a hydrogen

 So what does benzene look like??

Common Aromatic Compounds

 Include Aspirin and Vanillin (one of the flavour molecules in vanilla)

 You will notice many aromatic molecules are often depicted using a condensed structural formula except for the benzene ring, which is shown as a line structural formula.

29 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  This combination is commonly used by chemists, and we will use this method when drawing aromatics.

Naming Aromatics

1. If an alkyl branch is attached to a benzene ring, the compound is named as an alkylbenzene. Alternatively, the benzene ring may be considered as a branch of a large molecule: in this case, the benzene ring is called a phenyl branch.

2. If more than one alkyl branch is attached to a benzene ring, the branches are numbered using the lowest numbers possible, starting with one of the branches.

 Given the choice between two sets of lowest numbers, choose the set that is in both numerical and alphabetical order

Practice Naming Aromatics  Draw 1,2-dimethylbenzene

 Are there any isomers of this compound?

 There is also classical way of naming these isomers. The arrangements are denoted by the prefixe:s ortho (o), meta (m) and para (p). These names are still used in industry so you may encounter them in other references.

 Draw the line structural formula for 1-ethyl-3-methylbenzene, is there another possible name for this compound ?

 Draw the line structural formula for 2-phenylpentane

 Draw 3-phenylpent-2-ene

 Name the following

Summary

 We have now learned about both aliphatic and aromatic hydrocarbons. You will need to be comfortable naming all of the following:

Lesson 4 homework

 PG 53 Q 1-2

 Crude Oil Refining and Combustion

 Review Aromatic and Aliphatic Compounds

Properties of Organic Compounds & Crude Oil Refining

Lesson 5: Section 9.5 and 9.6 (pg. 386-400)

1) Compare boiling points and solubility of organic compounds

2) Describe fractional distillation and solvent extraction

3) Describe major reactions for producing energy and economically important compounds from fossil fuels

Physical Properties of Simple Hydrocarbons

Alkanes Non-polar molecules Only intermolecular forces are London Force Boiling point and melting point increase with number of carbons All insoluble in water (like dissolves like) – nonpolar and polar don’t mix 1-4Cs = gas, 5-16Cs = liquid 17 and up = solid at SATP Alkenes Non-polar molecules, therefore insoluble in water Boiling points slightly lower than alkanes with the same number of carbons due to less electrons (unsaturated), resulting in lower London Forces

34 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Alkynes Non-polar molecules, therefore insoluble in water Higher boiling points than alkanes and alkenes with similar C #s Accepted explanation: Linear structure around triple bond allows electrons to come closer together than in alkanes/enes, resulting in greater London Force In reality, triple bond gives these a higher boiling point than alkanes. Branching The more branching, the less significant the London Force (~lower b.p.) - more surface area in straight chain hydrocarbons allows more separation of charge, resulting in greater London Force - see Table #3 pg. 378 (i.e. pentane (with 5Cs) has a b.p. of 36oC which is much higher than dimethylpropane (5Cs) -12oC) = because branching decreased the strength of the London force

 London Forces – temporary dipoles resulting from an uneven distribution of e- in all molecules

 Temporary (-) end will repel e- in neighbouring molecules and so on

 Depends on size of molecule (number of e-’s)

 Weakest of the intermolecular forces

 Dipole-Dipole – only exists in polar molecules

 Attraction between + and – ends of molecule

 Hydrogen Bonding – super strong force

 Only exists when H-N, H-F, H-O bonds are present

Sample Question

 Predict the relative order of boiling points of the following compounds (lowest to highest). Explain your reasoning.

Methane Propane Hexane Decane

35 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Lowest ------> Highest

Reasoning:

 Which would be soluble in water?

Crude Oil Refining

 Crude oil is a complex mixture of hundreds of thousands of compounds, all of which have different boiling points

 We can take advantage of these different b.p.’s and physically separate the different components using heat

 This process is called fractional distillation or fractionation

 A fractional distillation tower contains trays positioned at various levels.  Heated crude oil enters near the bottom of the tower.  The bottom is kept hot, and the temperature gradually decreases toward the top of the tower.  As compounds cool to their boiling point, they condense in the cooler trays. The streams of liquid (called fractions) are withdrawn from the tower at various heights along the tower.

 A more detailed look…

 The vaporized components of the crude oil rise and gradually cool.

 To get from one level to the next, the vapours are forced to bubble through the liquid condensed in each tray.

 The figure shows the bubble caps used to allow this to happen.

 If a gas cools to its boiling point, it will condense and be piped out through the draining tube

Cracking

 Cracking: large hydrocarbons are broken into smaller fragments

 Historically, thermal cracking used extremely high temperatures but created large quantities of solid coke.

 Now, catalytic cracking uses a catalyst to speed up the reaction and produce less residual products like tar, asphalt and coke

 Example: C17H36(l)  C9H20(l) + C8H16(l) + C(s)

larger molecules  smaller molecules + carbon

 In 1960, hydrocracking was developed, which combines catalytic cracking and hydrogenation and produces no coke.

 Example: C17H36(l) + H2(g)  C9H20(l) + C8H16(l)

larger molecule + hydrogen  smaller molecules

Oil Refining

 The refining of crude oil can be divided into two main categories:

1. Physical Processes

 Fractional Distillation: see previous slides

 Solvent Extraction: solvent is added to selectively dissolve and remove an impurity or to separate a useful product from a mixture

2. Chemical Processes

 Cracking – larger molecules are broken down into smaller ones

 Reforming – large molecules are formed from smaller ones

38 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  These chemical processes are needed because fractional distillation does not produce enough of the hydrocarbons that are in demand (i.e. gasoline) and produces too much of the heavier fractions

Catalytic Reforming and Alkylation

 Catalytic Reforming: improves the quality of the gasoline

aliphatic molecule  aromatic molecule + hydrogen

 Alkylation: increases the branching; improves the quality of the fuel

aliphatic molecule  more branched molecule

 (AKA: isomerization because it converts molecules into a branched isomer)

Combustion Reactions

 Burning of hydrocarbons in the presence of oxygen

 Complete Combustion: abundant supply of oxygen; products are carbon dioxide, water vapour and heat

 Ex. C3H8(l) + 5O2(g)  3CO2(g) + 4H2O(g)

39 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Incomplete Combustion: limited supply of oxygen; products are carbon monoxide, soot (pure carbon) or any combination of carbon dioxide, carbon monoxide and soot in addition to water vapour and heat

 Ex. 2C8H18(l) + 17O2(g)  16CO(g) + 18H2O(g)

 OR 2C8H18(l) + 9O2(g)  16C(s) + 18H2O(g)

** Assume complete combustion unless specified otherwise

Balancing FYI

Ex. 2C8H18(l) + 17O2(g)  16CO(g) + 18H2O(g)

Can also be balanced using a fraction (you need to be

comfortable using this method) – divide each number by 2

Ex. 2C8H18(l) + 9O2(g)  16C(s) + 18H2O(g)

can also be balanced as …

LESSON 5 homework

 Hydrocarbon Review Table (next page)

 Concept Check and Quiz 1

 Functional Groups and Hydrocarbon Reactions

 Halides, alcohols, carboxylic acids, esters and polymers

40 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Addition, Substitution and Elimination, esterfication and polymerization

Hydrocarbon Description Example(s) (General Formula) ALKANES

CYCLOALKANES

ALKENES

CYCLOALKENES

ALKYNES

CYCLOALKYNES

AROMATICS

Organic Chemistry: Part 2

Organic Halides and Alcohols

Lesson 6: Section 10.2 and 10.3 (pg. 417-435)

1) Name and draw structural, condensed structural and line diagrams and formulas for organic halides and alcohols

2) Identify types of compounds from their functional groups, given the structural formula and name of the functional groups

Organic Halides

 Organic compounds where one or more hydrogen has been replaced with halogens (F, Cl, Br, I)

 Common example: CFC (chlorofluorocarbons)

 Nomenclature is similar to naming branch chains of hydrocarbons, but the branch name used is based on the halogen used

 chloro-, fluoro-, bromo-, iodo-

 What do you need to know about organic halides?

 May by polar or nonpolar molecules or may have a relatively nonpolar (hydrocarbon) end and a polar (halide) end (**Remember Electronegativity differences)

 Have higher boiling points than similar hydrocarbons

 Have very low solubility in water but higher solubility than similar hydrocarbons

 Are typically good solvents for organic materials such as fats, oils, waxes, gums, resins or rubber

 Usually toxic or ecologically damaging (DDTs and PCBs)

Practice Drawing Organic Halides

 Draw 1,2-dichloroethane

 Draw 2,2,5-tribromo-5-methylhexane

Practice Naming Organic Halides

 Name the following:

CH2Cl2

Alcohols

 An alcohol is an organic compound that contains the –OH functional group (hydroxyl)

44 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  General formula is R-OH (R = rest of molecule)

 Alcohols are classified as primary, secondary or tertiary depending on the number of carbons bonded to the carbon that contains the hydroxyl group

Common Alcohols

 Methanol (also called wood alcohol) is extremely toxic, causing death and blindness

 Ethanol (also known as grain alcohol) is the alcohol found in alcoholic beverages and is used in the production of vinegar

 Gas line antifreeze, windshield de-icer, windshield washer fluid – all contain methanol

Naming Alcohols

45 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 1. Locate the longest chain that contains an –OH group attached to one of the carbon atoms. Name the parent alkane

2. Replace the –e at the end of the name of the parent alkane with –ol (i.e. butane becomes butanol)

3. Add a position number before the suffix –ol to indicate the location of the –OH group

REMEMBER to number the main chain of the hydrocarbon so that the hydroxyl group has the lowest possible position numb

4. If there is more than one –OH group (called polyalcohols), leave the –e in the name of the parent alkane and put the appropriate prefix before the suffix –ol (i.e. diol, triol, tetraol)

5. Name and number any branches on the main chain. Add the names of these branches to the prefix.

Draw 2,3-dimethylbutan-2-ol

Draw line structural formulas for:

1. Cyclohexanol

2. Phenol

3. The three structural isomers of C5H11OH that are pentanols

 What do you need to know about alcohols?

Question: Why is the propane used in a barbecue a gas at room temperature, but propan-2-ol (also known as rubbing alcohol) a liquid at room temperature?

 What do you need to know about alcohols?

Question: Glycerol (propane-1,2,3-triol) is more viscous than water, and can lower the freezing point of water. When added to biological samples, it helps to keep the tissues from freezing, thereby reducing damage. From your knowledge of the molecular structure of glycerol, suggest reasons to account for these properties of glycerol.

48 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Application Question

 Predict the order of increasing boiling points for the following compounds, and give reasons for your answer.

butan-1-ol pentane 1-chlorobutane

Lesson 6 homework

 Due tomorrow

 Carboxylic Acids and Esters

Organic Chemistry:

Carboxylic Acids and Esters

LESSON 7: Section 10.4 (pg. 436-443)

1) Name and draw structural, condensed structural and line diagrams and formulas for carboxylic acids and esters

2) Identify types of compounds from their functional groups, given the structural formula and name of the functional groups

Carboxylic Acids

 A carboxyl group is composed of a carbon atom double bonded to an oxygen atom and bonded to a hydroxyl group (-COOH)

 Note: Because the carboxyl group involves three of the carbon atom’s four bonds, the carboxyl is always at the end of a carbon chain or branch

Naming Carboxylic Acids

1. Name the parent alkane

2. Replace the –e at the end of the name of than parent alkane with –oic acid

3. The carbon atoms of the carboxyl group is always given position number 1. Name and number the branches that are attached to the compound.

Draw 3-methylbutanoic acid

51 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Draw trichloroethanoic acid (key ingredient in chemical peels)

CCl3COOH

Draw 3-propyloctanoic acid

Esters

 The reaction between a carboxylic acid and an alcohol produces an ester molecule and a molecule of water

 This reaction is known as a condensation or esterification reaction

 The ester functional group –COO– is similar to that of a carboxylic acid, except that the H atom of the carboxyl group has been replaced by a hydrocarbon branch.

52 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Esters are responsible for natural and artificial fragrance and flavourings in plants and fruits.

 In naming an ester you have to recognize that an ester has 2 distinct parts. The main part contains the C=O group which comes from the parent acid. The second part is the alkyl group.

Naming Esters

1. Identify the main part of the ester, which contains the C=O group. This part comes from the parent acid.

2. Begin by naming the parent acid but replace the –oic acid ending of the name with –oate. (propanoic acid becomes propanoate)

3. The second part is the alkyl group that is attached to the single oxygen atom. Name this as you would any other alkyl group (in this case = methyl)

4. Put the names together. Note that esters are named as two words.

Name the following ester and the acid and alcohol from which it can be prepared.

Name the following ester and the acid and alcohol from which it can be prepared

Lesson 7 homework

 Organic Reactions

 Summary and Review of all organic molecules

 Full Naming Quiz (in two days)

Review – Functional Groups

Physical Properties of Hydrocarbon Derivatives

Halides higher boiling points than hydrocarbons (1-12Cs are liquids at SATP) due polarity of many of the molecules

Even though these molecules are polar, they are insoluble in water as they are more attracted to themselves then the water molecules.

Alcohols Much higher boiling points than hydrocarbons (1-12Cs are liquids at SATP) due to hydrogen bonding between hydroxyl groups of adjacent molecules

Small alcohols are totally miscible in water, but the larger the hydrocarbon part of the

55 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 alcohol (nonpolar part), the more nonpolar the alcohol is

Carboxylic AcidsLike alcohols they have hydrogen bonding, but is more significant due to the C=O. This means greater bps and solubility than alcohols with same number of Cs.

Carboxylic acids with 1-4Cs are

completely miscible in water, but like alcohols decrease as the non-polar end gets larger

Compound Boiling Point (oC)

butane -0.5

butan-1-ol 117.2

butanoic acid 165.5

Esters Fruity odour in some cases

Polar but they lack the –OH bond therefore do not have hydrogen bonding, so lower bps than both alcohols and carboxylic acids

Esters with few carbons are polar enough to be soluble in water HYDROCARBON DERVIVITIVES SUMMARY TABLE

Hydrocarbon Description Example(s) (General Formula) Organic Halides

Alcohols

Carboxylic Acids

Esters

Hydrocarbon Reactions:

Addition, Substitution and Elimination

Today’s Objectives: Section 10.2,10.3 and 10.4 (pg. 419-444)

1) Define, illustrate and provide examples of simple addition, substitution, elimination and esterification (condensation)

2) Predict products and write and interpret balanced equations for the above reactions

Hydrocarbon Reactions

1. Addition

alkenes and alkynes + H2(g)  alkanes (hydrogenation)

alkenes and alkynes + HX (or X2)  organic halides

57 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 2. Substitution

alkanes and aromatics + X2  organic halides

3. Elimination

alcohols  alkenes + water (dehydration)

organic halides + OH-  alkenes + halide ion + water

4. Esterification (already covered, just review)

carboxylic acid + alcohol  ester + water

5. Polymerization – monomer + monomer = polymer

addition and condensation

1. Addition Reactions: reaction of alkenes and alkynes with hydrogen gas, a halogen compound, a hydrogen halide compound or water.

 Addition reactions usually occur in the presence of a catalyst

 Changes the saturation of the molecule (unsaturated → saturated)

a) Addition with H2(g) (also called hydrogenation)

b) Addition of a halogen

c) Addition of an HX (hydrogen halide) molecule

 Show both possible isomers when predicting the products

d) Addition of water an alkene

Practice Addition Reactions

 For each of the following questions, draw condensed structural diagrams and name all products

1. ethene + bromine 

2. hydrogen chloride + ethene 

3. 3-methylbut-1-yne + excess hydrogen 

61 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 4. Pent-2-ene + water 

2. Substitution Reactions – breaking of a C-H bond in an alkane or an aromatic ring and replacing it with another atom or group of atoms

 Usually occur slowly at room temperature, so light may be necessary as a catalyst

 Often substitutes a halogen for a hydrogen

 No change in saturation (saturated → saturated)

2. Substitution Reactions – breaking of a C-H bond in an alkane or an aromatic ring and replacing it with another atom or group of atoms

Practice Substitution Reactions

 For each of the following questions, draw condensed structural diagrams and name all products

1. propane + fluorine 

2. ethane + chlorine 

3. Elimination Reactions – involves eliminating atoms or groups of atoms from adjacent carbon atoms; decreases the level of saturation

a) Alkane cracked into an alkene (uses high temperatures)

b) Alcohol is reacted with a catalyst to produce an alkene and water (dehydration – removes a water molecule from the alcohol)

c) Alkyl halide reacts with a hydroxide ion (OH-) to produce an alkene (dehydrohalogenation – removes a hydrogen and halogen atom)

Practice Elimination Reactions

1. Write a structural formula equation for the preparation of but-2-ene from chlorobutane, in the presence of a strong base

2. Write a structural formula equation for the preparation of but-2-ene from butan-2-ol

Reaction type Complete Addition Elimination Substitution Esteri-fication Combustion

Reactants

Products

Day 8 Homework

 Pg. 422 #7,8 (Addition and Substitution)

 Pg. 433 #18-19 (Elimination)

 Pg. 443 #1, 5-8 (Esterfication)

What is coming up tomorrow?

 Polymerization

 STS Connections

Organic Chemistry:

Polymerization Reactions

Today’s Objectives: Section 10.5 (pg. 445-459)

1) Define, illustrate, and give examples of monomers, polymers, and polymerization in living and non-living systems

STS: 2) Illustrate how science and technology are developed to meet societal needs and expand human capabilities

STS: 3) Illustrate how science and technology have both intended and unintended consequences

Polymerization

 Polymers are large molecules made of chains of monomers, small molecules that link together.

 Polymerization is the formation of polymers from these small units

67 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Polymers can occur naturally (proteins, carbohydrates) and can be synthesized (nylon, Teflon, polyethylene)

 They play an integral part in the function of life systems and have revolutionized the way society functions

Addition Polymerization

 Many plastics (synthetic polymers) are made by this process

 The polymerization process is initiated with a free radical (a species with an unpaired electron). The free radical attacks and breaks the double bond forming a new free radical that attacks another monomer

Addition Polymerization always results in one product, the polymer

68 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Requires unsaturated hydrocarbon monomers and bond saturation occurs when the polymer is made

 Common polymers produced by addition polymerization:

Things to know about addition polymers…

 The polymer names end in –ene (i.e. polystyrene, polypropene). Does this mean they have double bonds?

 What properties make Teflon a good product for non-stick materials?

Condensation Polymerization

 Monomers combine to form a polymer and a bi-product. Each time a bond forms between monomers, small molecules, such as water, ammonia, or HCl are “condensed” out.

The polymerization of nylon:

 Condensation polymerization also produces natural polymers, called proteins.

 Amino acids (monomers) polymerize to make peptides (short chains of amino acids) or proteins (long chains of amino acids)

70 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017 Comparison of Addition and Condensation Polymerization

Polyester

 When a carboxylic acid reacts with an alcohol in an esterification reaction, a water molecule is eliminated and a single ester molecule is formed.

 This esterification reaction can be repeated so many esters are joined in a long chain… a polyester

 This is created using a dicarboxylic acid (an acid with a carboxyl group at each end) and a diol (an alcohol with a hydroxyl group at each end)

 The ester linkages are formed end to end between alternating acid and alcohol molecules

Polyester: Dacron

 Another example of a polyester:

 Note the two carboxyl groups in the dicarboxylic acid and the two hydroxyl groups in the polyalcohol that start the chain reaction

Most synthetic polymers have a natural counterpart 

 Starch, wood, silk, DNA

Day 9 Homework

 Pg. 448 #2-4

 Pg. 452 #13

 Pg. 455 #16, 17

 Due tomorrow

What is coming up tomorrow?

72 | P a g e CHEMISTRY 30 – UNIT C – CHEMICAL CHANGES OF ORGANIC COMPOUNDS Spring 2017  Labs ?

 Chapter 10 Exam

 Assignment #2 Due

 KIM Sheets

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