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Additional Structures to Accompany Exp. 16

Introduction to Models

Goals:

  • Draw formulas for alkanes from their three-dimensional models.
  • Write the names of alkanes from their structural formulas.
  • Construct models of isomers of alkanes.
  • Write structural formulas for designation of functional groups.

Introduction: The saturated hydrocarbon represents a group of organic compounds composed of carbon and hydrogen. Alkanes and cycloalkanes are called saturated hydrocarbons because their carbon atoms are connected by only single bonds. In each type of alkane each carbon must have four valence electrons and must always have four single bonds.

To learn more about the three dimensional structure of organic compounds, it is helpful to build models using ball and stick model kit. In the kit are wooden (or plastic) spheres which represent the typical elements in organic compounds. Each wooden atom has the correct number of holes drilled for bonds that attach to other atoms.

Table 16A.1 Elements and Bonds Represented in the Organic Model Kit

Color / Element / Number of Bonds
Black / Carbon / 4
Yellow or White / Hydrogen / 1
Red / Red / 2
Green / Halogen (F, Cl, Br, or I) / 1
Blue / Nitrogen / 3
Silver / Hexavalent (not used) / 6
Longer bonds or springs / C, N, O / Multiple (double or triple)
Shorter bonds or sticks / Any / Single bonds
  1. First we will build methane, CH4. We will also show the three ways to draw this structure.

A)3-dimensional

B)Complete Structural formula

C)Condensed structural formula

Table 16A.2 Complete the table by drawing the first 10 Alkanes:

Name / Condensed formula / Complete structural Formula / Draw at least one isomer AND name it
Methane / CH4 / Name: ______
Ethane / CH3CH3 / Name: ______
Propane / Name: ______
Butane / Name: ______
Pentane / Name: ______
Hexane / Name: ______
Heptane / Name: ______
Octane / Name: ______
Nonane / Name: ______
Decane / Name: ______

Table 16A.3 Fill in the table and find the functional groups:

Condensed formula / Full Structural Formula / Organic Family (functional group)
CH3-OH
CH3-CH2-CH3
CH2=CH2
CH3-O-CH3
O
CH3-C—OH
CH3-NH2
O
CH3-C-CH3
O
CH3-N-CH3
CH3-CH2-CH=CH-CH3
CH3-CH2-NH-CH2-CH3
CH3-CH2-O-CH3
CH3CH2CH2COOH

Additional Structures to Accompany Lab 18

Structures of Alkanes

Goals:

  • To determine names and shapes of halogenated organic compounds
  • To determine the name and shape of cycloalkanes
  • To determine the name and shape of branched alkanes

Table 18A.1 Complete the table for the haloalkane

Name / Complete Structural formula / Condensed structural formula
Chloromethane
1,2-dibromoethane
2-iodopropane

Table 18A.2 Complete the table by creating four isomers of dichloropropane

Name / Complete structural formula / Condensed structural formula

Table 18A.3 Complete the table by creating the cycloalkane with the appropriate number of carbons.

Number of C atoms / Name / Condensed structure / Geometric Formula
3 /
4
6
8

Table 18A.4 Complete the table

Name / Condensed Structure / Complete Structural Formula / Geometric formula (if applicable)
ethyne /
2-methyl-2-pentene
phenol

ADDITIONAL STRUCTURES FOR

ALCOHOLS AND PHENOLS

LAB 19

Goals:

  • Determine chemical and physical properties of alcohols and phenols
  • Classify an alcohol as primary, secondary, or tertiary
  • Name and build models of various alcohols

Introduction: Alcohols are organic compounds that contain the hydroxyl group (-OH). The simplest alcohol is methanol. Ethanol is found in alcoholic beverages and preservatives and is used as a solvent. Isopropanol or 2-propanol is used as a disinfectant and is found in perfumes. The abbreviations for alcohols may be MeOH for methanol or EtOH for ethanol. What would be the abbreviation for n-propanol?

Table 19A.1 Fill in the table for the simple alcohols listed.

Name / Condensed Structure / Complete Structure
Methanol
Ethanol
Isopropanol or 2-propanol

A benzene ring with a hydroxyl group is known as phenol. Concentrated solutions of phenol are caustic and cause burns. It is a weak acid that is soluble in water. However, derivatives of phenol, such as thymol, are used as antiseptics and are sometimes found in cough drops.

Table 19A.2 Fill in the table for these aromatic alcohols

Name / Condensed Structure / Complete Structure
Phenol
Thymol (2-isopropyl-5-methylphenol)

Thiols and Diols: A thiol contains an –SH group. The name is given the alkane chain name then thiol is after it as one word. Ex. CH3CH2SH is ethanethiol

Diols contain TWO –OH groups. We will not be naming diols, but you should know what they are and how to recognize this functional group.

Classification of Alcohols: In a primary (10) alcohol, the carbon atom attached to the –OH group is bonded to one other carbon atom. In a secondary (20) alcohol, it is attached to two carbon atoms and in a tertiary (30) alcohol to three carbon atoms.

Table 19A.3 Fill in the table describing if the alcohol is primary, secondary, or tertiary.

Name / Condensed structure / Complete structure / 10, 20, or 30
Ethanol
t-butyl alcohol (2-methyl-2-propanol
1-methylcyclopentanol
3-pentanol
Cyclohexanol

Table 19A.4 Fill in the missing information in the table below.

Name / Condensed formula / Complete formula / Functional group or Organic family
3,4 di-methylhexane
2,2,4-trimethylhexane
3-ethyl2,4,5-trimethylhexane
1-ethyl-3-methyl-5-propylcyclohexane
4-chloro-4,5-dimethyl-2-hexene

ETHERS

Ethers contain an oxygen atom that is attached by a single bond to two carbon groups that are alkyls or aromatic rings. Ethers have a bent structure like water and alcohols. Most ethers are named by their common names. The IUPAC names are used only when the ether is more complex.

Step 1 For simple ethers, use the common name. Write the name of each alkyl or aryl (aromatic) group attached to the oxygen atom in alphabetical order followed by the word ether.

Step 2 For more complex ethers, use IUPAC naming. Use the alkane name of the larger alkyl group as the main chain. Name the oxygen and smaller alkyl group as a substituent called an alkoxy (alkyl + oxygen) group.

Step 3Number the main chain beginning at the end nearest the alkoxy group and give the location of the alkoxy group on the main chain.

Ex. CH3-O-CH3 = dimethyl ether (common name)

Ex.

-O – CH3 methoxycyclobutane (IUPAC) or cyclobutyl methyl ether (common)

19A.5 Fill in the table for the following ethers

Common name / IUPAC name / Condensed Structure / Complete Structure
Methoxymethane
Diphenyl ether
Ethoxyethane
/ 2-methoxybutane
Ethyl propyl ether

Additional Structures for Lab 20

Aldehydes and Ketones

Goals:

  • Write functional groups of aldehydes and ketones
  • Determine chemical and physical properties of aldehydes and ketones
  • Name and create models of aldehydes and ketones

Introduction:

Structures of some Aldehydes and Ketones: Aldehydes and ketones contain the carbonyl group. In an aldehyde, the carbonyl group has a hydrogen attached; the aldehyde functional group occurs at the end of the carbon chain. In a ketone, the carbonyl group is located between two of the carbon atoms within the chain.

Write the generic form of aldehydes: ______

Write the generic form of ketones: ______

Properties of Aldehydes and Ketones: Many aldehydes and ketones have sharp odors. If you have taken biology class, you may have noticed the odor of FormalinTM, which is a solution of formaldehyde. When you remove fingernail polish, you may notice the strong odor of acetone, the simplest ketone, which is used as a solvent. Aromatic aldehydes have a variety of odors. Benzaldehyde, the simples aromatic aldehyde, has an odor of almonds.

Table 20A.1 Fill in the missing information in the table

Name / Condensed Formula / Complete structural formula
Formaldehyde
IUPAC name: ______
Acetaldehyde
IUPAC name: ______
Acetone
IUPAC name: ______
Butanone
IUPAC name: ______
Cyclohexanone

Benedict’s test is used to distinguish aldehydes from ketones. When in contact with an aldehyde the oxidiation occurs because the Cu2+ bluish ion contained in Benedict’s solution becomes a reddish Cu+ (reduced). The copper cation is reduced whereas the aldehyde is oxidized. Ketones cannot oxidize so the copper ion remains blue.

Table 20A.2 Fill in the following table

Name / Condensed Formula / Complete Structural Formula / Functional Group
CH3CH2CCH
3-methylcyclohexene
Trans-2-pentene
m-ethyltoluene
2,2,5-trimethylcyclohexanol
CH3CH2CH2SH

Begin working on the structures in your lab practical review. Try to do as many as you can without looking up the structures.