domingo, 15 de julio de 2012

Amines

Definition: Are organic compounds that contain a nitrogen.
Least organic compounds:
 Primary amine: Methylamine
 Secondary amine: Dimethylamine
 Tertiary amine: Trimethylamine
Functional group:

Primary amine: R-NH2

Secondary amine: R2-NH

Tertiary amine: R3-NH

Esters

Definition: Are organic compounds derived from carboxylic acids. A carboxylic acid contains the -COOH carboxyl group, and in an ester the hydrogen in the group is replaced by a hydrocarbon group of some kind. This could be an alkyl group like methyl or ethyl, or one containing a benzene ring like phenyl.
Least organic compound: Methylmethanoate COOHCH3
Functional group:

O = C - O - R
R   .

Physical properties:
Boiling pointsThe small esters have boiling points which are similar to those of aldehydes and ketones with the same number of carbon atoms.
Molecule
Type
Boiling point
CH3COOCH2CH3
Ester
77,1
CH3CH2CH2COOH
Carboxylic acid
164
Solubility in water
The small esters are fairly soluble in water but solubility falls with chain length.
Molecule
Type
Boiling point
CH3COOCH2CH3
Ester
77,1
CH3CH2CH2COOH
Carboxylic acid
164 


Carboxylic acids

Definition: Are organic compounds containing a carboxyl group attached to it.
Least organic compound: Methanoic acid COOH
Functional group:

R - C = O
O

Physical properties: The boiling points of carboxylic acids of similar size are higher still. The reason for the solubility is that although aldehydes and ketones can't hydrogen bonds with themselves, they can hydrogen bond with water molecules. The carboxylic acids with up to four carbon atoms will mix with water in any proportion.

IUPAC name
Molecular weight
Boiling point
Formula
Butane
58
0
CH3CH3CH2CH3
Propanol
60
97
CH3CH2CH2OH
Ethylmetherether
60
6
CH3-O-CH2CH3
Propanal
58
49
CH3CH2CH=O
Propanoic acid
60
118
CH3CH2COOH




Aldehydes and Ketones

Aldehydes definition: Are compounds containing a carbonyl group with at least one hydrogen attached to it.
Least organic compound: Methanal O=CH2

Ketones definition: Are compounds containing a carbonyl group with two hydrocarbons attached to it.
Least organic compound: Ethanone CH2-CH=O

Structure: They are organic compounds which incorporate a carbonyl group, that is functional, C=O. The carbon atom has two remaining bonds that may be occupied by hydrogen or arkyl or aryl substituents. If, at least one of these is hydrogen, it is an aldehyde. If neither is hydrogen, it is a ketone.

R1    .
 C = O
R2    .

Physical properties: They can H-bond with water, because they have an O atom. The small ones are freely soluble in water, but solubility falls with chain length. The reason for solubility is that although they can't H-bond with themselves, they can with water molecules.

IUPAC name
Molecular weight
Boiling point
Formula
Butane
58
0
CH3CH3CH2CH3
Propanol
60
97
CH3CH2CH2OH
Ethylmetherether
60
6
CH3-O-CH2CH3
Propanal
58
49
CH3CH2CH=O




lunes, 7 de mayo de 2012

Thiols

They are compounds containing an -SH (sulfydryl) group.

Physical properties:
 - Hydrogen bonding is much weaker that that in alcohols.
 - Lower boiling points that similar alcohols.
 - Less soluble in water and other polar solvents than comparable alcohols.
 - Low-molecular-weight thiols stink.
 - Responsible for smells such as those from rotten eggs and sewage the scent of skunks is due primarily to these two thiols.

Chemical properties:
 - 5-Bonds are longer and weaker than those to oxygen.
 - 5-H bonds are non-polar covalent since 5 is less electronegative than O.
 - No hydrogen bonding.
 - Lower boiling points that comparable alcohol.

An example:

   

 Condensed formula: CH3-CH2-SH

 IUPAC Name: Ethanethiol

 Common Name: Ethylmercaptan


Ethers

They are organic compounds in which oxygen is bonded to two carbon groups, alkyl groups.

Functional group:                    R-O-R

Physical properties:
 - Ethers have no H atoms bond to the O atom as in alcohols.
 - Therefore molecules in the pure liquid are incapable of hydrogen bonding.
 - Ethers have similar boiling points to alkanes of comparable molecular weigth.
 - Not soluble in water.

Chemical properties:
 - Ethers are flammable.

                                                        CH3-O-CH3
            Common name                                                             IUPAC name 
             Dimethylether                                                              Methyoxymethane


Alcohols

They are organic compounds that contain a Hydroxyl group (-OH) attached to a hydrocarbon.
Most of the alcohols are colorless liquids. Methyl alcohols, ethyl alcohol are liquids with fruty odors The higher alcohols those containing 4-10 carbon atoms are somewhat viscous, or oily and tey have hevier fruty odors, some of the highly branched alcohols and many alcohols  containing more than 12 carbon atoms are solid at room temperature.


Physical properties:
 - Most of the alcohol are colorless liquids at room temperature.
 - Methyl alcohol, ethyl alcohol, and isopropyl alcohol are liquids with fruity odors.
 - Alcohol that rank from 4 to 10 carbons are viscous or oily.
 - Some of the highly branched alcohols and many alcohols containing more than 12 carbon atoms.


Chemical properties:
 - Alcohols are flammable. They have a lower boiling point than similar hydrocarbons.

Types of alcohols


 - Primary alcohol
          H                R= radical
      H-C-OH        H= hydrogen
          R

 - Secondary alcohols
         H
     R-C-OH
         R

 - Tertiary alcohols
         R
     R-C-OH
         R

An example:

 IUPAC Name: Ethanol