Chpt. 22: Some Families of
Organic Compounds
(Organic Chemistry)
Previously studied organic families:
Alkanes
Alkenes
Alkynes
Aromatic Compounds
This section involves the study of further organic
families:
Chloroalkanes
Alcohols
Aldehydes
Ketones
Carboxylic Acids
Esters
All ten of these families can be split into two groups:
Group 1 – Tetrahedral
*Do Not Take Diagram
Group 2 – Planar
*Do Not Take Diagram
Group 1: Tetrahedral
Group 2: Planar
 Alkanes
 Alkenes
 Chloroalkanes
Alcohols
 Alkynes
 Aldehydes
 Ketones
 Carboxylic Acids
 Esters
 Aromatic Conpounds
Tetrahedral Carbon Compounds
In saturated organic compounds, ALL of the carbon
atoms are tetrahedral
CHLOROALKANES:
Chloroalkanes are compounds in which one or more
of the hydrogen atoms in an alkane molecule have
been replaced by a chlorine atom
The part of an alkane remaining after one hydrogen is
removed is an alkyl group e.g. Methane CH4 minus a
hydrogen group leaves methyl -CH3
Remember: Alkyl Radicals
Name
Alkyl Radical
Methyl
CH3
Ethyl
C2H5
Propyl
C3H7
Butyl
C4H9
*Do Not Take This Slide
Chloroalkanes are named after the alkane from which
they are derived with the prefix chloro- indicating the
presence of chlorine.
Chloroalkanes of METHANE
Number
of
Chlorine
atoms
Name of
Compound
Chemical
Formula
1
Chloromethane
CH3Cl
2
Dichloromethane
CH2Cl2
3
Trichloromethane
(Chloroform)
CHCl3
4
Tetrachloromethane
CCl4
Structural
Formula
*Important Note*
You must be able to name and draw the structure of
all the chloroalkanes for the first four alkanes!!!
(methane, ethane, propane, butane)
Naming and Drawing structural formulas of Chloroalkanes:
1. Draw full structural formula of compound
2. Identify longest continous chain of carbon atoms parent alkane
3. Number carbon atoms from the end that gives lowest
number to the carbon atom to which the
chlorine atom is attached
4. Indicate position of chlorine atom e.g 2-chloro5. Name compound
Example:
Name the compounds:
a) CH3CH2CHClCH3
b) CH3CCl2CHClCH3
c) CH3CCl(CH3)CH3
Student Questions:
Workbook – pg 60 W22.1, W22.2, W22.3
Homework:
Book – pg 360 22.1,22.2, 22.3
Physical State and Properties of Chloroalkanes
• Chloroalkanes are slightly polar
• Chloroalkanes are insoluble in water but are soluble
in non-polar solvents e.g. cyclohexane,
methylbenzene
• Chloroalkanes have low boiling points but because
of the polarity of the carbon/chlorine bond
chloroalkanes have higher boiling points than
corresponding alkanes.
*Note: Boiling point depends on the strength of the
intermolecular forces, so, because longer carbon
chains have stronger van der Waals forces between
molecules they will have higher boiling points.
• Most chloroalkanes liquid at room temperature,
exception – chloromethane* and chloroethane are
gaseous
• Main use is as solvents:
- for removing oil and grease machinery, dry
cleaning
- paint stripper (dichloromethane)
- Tippex*
*Ozone Layer
Functional Group (Active Group)
A functional group is an atom or group of atoms
that defines the particular chemistry of a
homologous series.
Homologous Series
Functional Group
Alkanes
C-C single bond
Alkenes
C=C double bond
Alkynes
C=C triple bond
ALCOHOLS
Alcohols form a homologous series of compounds of
formula:
CnH2n + 1OH
• Functional group – OH group (V-shaped) called
hydroxyl group
AlcOHol
• Alcohols are formed when the hydrogen atom in
an alkane is replaced by the hydroxyl group (OH)
• Carbon atoms including that joined to the OH
group are *TETRAHEDRAL*
• Named by replacing -ane at end of corresponding
alkane with -ol
Primary, Secondary Tertiary Alcohols