organic chemistry

Organic Chemistry

The study of Carbon and its compounds

ORGANIC CHEMISTRY• The study of compounds containing Carbon

atoms. • Carbon has 4 valence electrons, always draw it

with 4 covalent bonds around it.• When it forms all single bonds the shape of

around the carbon is TETRAHEDRAL.

Properties

• Solubility– Most nonpolar (like dissolves like)– Most compounds are insoluble in water– Soluble in non-polar solvents

H

O

O

Properties

• Most are non-electrolytes– Covalent, no conductivity– (an exception is organic acids)

Properties

• Low Melting/ Boiling Points

Properties

• Rate of Reaction– Slower than inorganic compounds– High activation energy

Properties

• Bonding– Nonpolar covalent– Carbon has 4 valance electrons- tetrahedron– Carbon can bond with itself indefinitely (in dif.

shapes, many variations) Always make 4 bonds

C

HYDROCARBONS

• Compounds containing only C and H.• 3 open chain families• ALKANES• ALKENES• ALKYNES

Homologous Series or families

Group of related compounds in which each member differs from the next by one carbon and 2 hydrogens

Alkanes• Single-bonded hydrocarbons• Hydrocarbon= only carbon and hydrogen atoms

IUPAC name Molecular Formula Generic Formulamethane CH4

ethane C2H6

propane C3H8

butane C4H10

pentane C5H12

hexane C6H14 CnH2n+2

heptane C7H16

octane C8H18

nonane C9H20

decane C10H22

• As the molecular size and dispersion forces increase, the boiling point and freezing point increase

Table Q

Alkenes

• have one Double-bonded hydrocarbon• Unsaturated• Same prefix as alkanes, with suffix -ene

Dienes contain TWO double bonds, and are not

alkenes!

Alkynes

• one Triple-bonded hydrocarbon• Unsaturated• Same prefix as alkanes, and alkenes, with suffix -

yne

Saturated vs Unsaturated compounds

Single Bonds Double/Triple Bonds

Benzene•6 carbon atoms in a ring

Aromatic Hydrocarbon

Only structure really needs to be known for the regents.

Cyclic Hydrocarbons

June 2

• How to draw and name different organic compounds?

• ISOMERS• HW : Read Wkbk pg 194-197 #’s 1 TO 18

Isomers

• Compounds with:• the same molecular formulas • different structural formulas

C4 H10

Normal Butane 2-Methyl Propane

Although these structures look different, they both have the same molecular formula of C4 H10

ISOMERS

• Same molecular formula but different structural formula. Have different chemical and physical properties.

Alkyl Groups

• Have 1 less hydrogen (H) than the corresponding alkane

• Ex:• Methyl CH3 – 1 less H than CH4

• Ethyl C2H5 – 1 less H than C2H6

Rules for naming organic compounds

For Straight or continuous chains: normal form n-alkanes.

For branched compounds:1.Find the longest continuous chain and name the

compound. Branches are alkyl groups and end with –yl. 2. The location of the alkyl group is determined by

assigning numbers to the carbon atoms of the longest chain, beginning at the end that will give the lowest number to the carbon that contains the alkyl or special group.

Drawing Rules

Step 1 Step 2-ane, Alkane: draw all single bonds

-ene, Alkene: draw all single bonds except draw a double on the number carbon that is present in the name

-yne, Alkyne: draw all single bonds except draw a triple bond on the number carbon that is present in the name

Step 3It’s as easy as 1, 2, 3….

Make sure all carbons have 4 bonds

Draw Hexane

1st Task:Draw Hexane

CCCCCC

Condensed Formula: CH3-CH2-CH2-CH2-CH2-CH3

Draw 1-Pentene

2nd Task:-ane, Alkane: draw all single bonds

-ene, Alkene: draw all single bonds except draw a double on the number carbon that the prefix shows

-yne, Alkyne: draw all single bonds except draw a triple bond on the number carbon that the prefix shows

-ene, Alkene: draw all single bonds except draw a double on the number carbon that the prefix shows

Draw 2-butyne

3rd Task:-ane, Alkane: draw all single bonds

-ene, Alkene: draw all single bonds except draw a double on the number carbon that the prefix shows

-yne, Alkyne: draw all single bonds except draw a triple bond on the number carbon that the prefix shows

-yne, Alkyne: draw all single bonds except draw a triple bond on the number carbon that the prefix shows

-yne, Alkyne: draw all single bonds except draw a triple bond on the number carbon that the prefix shows

Draw: 2, 3-dimethylbutane

Practice Problems• Using Table Q, what type of homologous

structure is this and why?

Why?•General formula•Structure•Name

June 4

• Objective : Functional groups . • How to distinguish them and what do they do

to an organic compound?• Table R• HW P 201-204 #’s 34 TO 48

Table ROrganic compounds and their

functional groups

Halides (Halocarbons)

• A halide is formed when one or more halogen elements attach themselves to a chain of carbons atoms

• Halogen include all the elements in group 17

Naming Halocarbons

• Halocarbons are usually formed from Alkenes– This is because the double bonds that are present

break; leaving empty bonds on the carbons where the halogens are now able to form

Double Bond

Naming Halocarbons

• Every halogen has its own prefix to put at the beginning of its name– It is listed in Table R

• When the bonds brake;the halogens fill the empty space

Alcohols

• Contain 1 less Hydrogen and in its place there is an –OH group instead.

• Even though alcohols have an –OH group, they are not considered a base.– This is because there are covalent bonds holding

the –OH to the carbons and bases don’t have covalent bonds present on the –OH.

– When in solution, acids only release an H+ and bases release OH-

Naming Alcohols• You start with Alkane. (In this case, Methane)• Take away one of the Hydrogen atoms.• Add an –OH group to the empty space• For the name; drop the –e at the end of the prefix

(Methane) and add –ol to name the Alcohol!

Ether

• In an ether, there is always an oxygen atom in between two carbons.

• And there can be any number of carbons on each side of the oxygen.

Naming Ethers• Count the amount of carbons on the left side

of the Oxygen first.• Count the number of carbons on the right side

of the oxygen.• The carbons on the left make Methyl and the

carbons on the right make Ethyl, then put Ether at the

end.

Aldehyde

• Aldehydes are known when there is one double bonded oxygen atom at the beginning or the end of a carbon chain.

Forming Aldehydes• Start with a carbon chain (butane).• Drop off two Hydrogen atoms.• Add a double bonded oxygen to the open

carbon.

Name It!• Four Carbons = butane• Since all aldehydes end in –al. Drop the –e

and add –al to the end.

Ketone

• Ketones can be identified by the oxygen double bonded to a carbon in the middle of a carbon chain.

Name a Ketone

• We have a chain of carbons (4=butane)• If the double bonded oxygen is found in the

middle of a carbon chain then it is a ketone and the –e must be dropped and add –one in its place

Organic Acids!!!!!!• Contains a double bonded oxygen and an –OH to the

last carbon in the chain• Called acids because H+ ions are released when

dissolved in water• Since ions are present when dissolved, an electric

current can be conducted through the water• Organic acids are electrolytes!

Name the acid

• HexaneDrop off the three hydrogen atoms at the end of the chainAdd a double bonded oxygen atom

and an –OH group to the open carbon atom

REMOVE: -e

ADD: -oic Acid

AND THERE YOU HAVE IT!!

Start with the carbon chainForm the Acid

Ester• Esters have two oxygen atoms present– One is connected by double bonds to a carbon atom– The other is connected by single bonds but to two carbon

atoms• An ester is formed from the reaction of an acid and an

alcohol.

And Esters

smell

goood!!

Title it!-count the number of carbons on the side that is only touching one carbon.

-Add –yl as the suffix.

-Now count the number of carbons in the chain attached to the two oxygen atoms.

-All that’s left is to add –oate to the end

Amine

• Amines contain a nitrogen atom– the nitrogen atom is found at the end of a carbon

chain; attached to one carbon as well as two hydrogen.

Naming the Amine is easy

• There are only two steps involved!– Count the hydrocarbons– Drop the –e and add –amine

Amide

• Amides also contains a Nitrogen atom but attached to the same carbon is a double bonded oxygen.

How do I name it??

• Amides are just the same as naming the amines except instead of adding –amine, you are adding –amide.

Amino Acids

Amino Acids…

• Contains both an amine and an organic acid

Amine

Organic Acid

NOTE: All the example on how the groups are named are shown on table R in the far right column.

Note: The formulas on how each group is drawn is shown in the formula column.

June 6

• OBJECTIVE: ORGANIC REACTIONS• Read pgs 206-208 #’s 49 to 63• TAKE HOME TEST• P 210 ANSWERS IN SCANTRON Q 1TO 30

Organic Reactions

1.CombustionTABLE I the first 6 rxn are

combustions• Burning (reaction with oxygen)• Hydrocarbons burn to form carbon dioxide

and water

Organic (hydrocarbon) + O2 CO2 +H20Organic (hydrocarbon) + O2 CO2 +H20heat

Test to show if there is Carbon Dioxide: Limewater (colorless) turns a milky white color with Carbon dioxide

In a limited supply of oxygen, C and CO are formed

2. Substitution

• Replacement of one or more hydrogens in a saturated hydrocarbon by a halogen.

Alkane + halogen(X2) halocarbon + HX(g)

+ F2 + HFF

3.Addition

• Adding one or more atoms at a double/ triple bond . Could be Hydrogenation (add H)Or Halogenation (add halogens)For alkenes and alkynes!

+ F2

F F

H H

4.Esterification

• Acid and alcohol produce ester and water

Fats are Esters derived from glycerol (a trihydroxy alcohol- has 3 OH groups) and long fatty acids

GlycerolFats are Esters derived from glycerol (a trihydroxy alcohol- has 3 OH groups) and long fatty acids

5.Saponification

• (hydrolysis) Ester breaks up into Acid and Alcohol (reverse of esterification)

• Produces soap

Fat + Strong Base Soap + Glycerol

6.Fermentation

C6H12O6 -------------> 2 C2H5OH + 2 CO2

Zymase (enzyme)

Glucose Ethanol Carbon Dioxide

7 POLYMERIZATION

• Polymers are made of chains of smaller units called MONOMERS

• NATURAL POLYMERS• Protein, starches, cellulose• SYNTHETIC POLYMERS• Nylon, rayon, polyethylene

7.Polymerization

• Small molecules join together to form bigger molecules (monomers to polymer)

amino acid + amino acid + amino acid proteinmonomer + monomer + monomer polymer

Polymerization

• 2 Types:• Condensation Polymerization: –Dehydration synthesis, occur when water is

removed from primary alcohols. Have ether or ester linkages. –Make water and polymer

• Addition Polymerization– Monomers join together by breaking a

double/triple bond

n nnumber of ethene join together number of polyethylene

Finding missing reactants and products in Organic Reactions

• # of atoms on the left side of the arrow must equal # on the right

• After the elements/compounds are correctly written, change the coefficient

• Ex:• C2H6 + Cl2 C2H5Cl + ______

HCl

Practice Regents Questions

• Go online to regentsprep.org!• http://regentsprep.org/Regents/core/questio

ns/questions.cfm?Course=CHEM&TopicCode=06

• http://reviewgamezone.com/game.php?id=669

• http://www.youtube.com/watch?v=1qGPWdm2MlI