This document provides an introduction to organic chemistry, focusing on hydrocarbons. It defines organic chemistry as the study of carbon-containing compounds, of which over 90% are organic. The key types of hydrocarbons discussed are alkanes (containing only single bonds), alkenes (containing carbon-carbon double bonds), and alkynes (containing carbon-carbon triple bonds). The document outlines methods for naming and drawing structural formulas of straight-chain and branched alkanes, as well as alkenes and alkynes.
2. Organic Chemistry
- is the study of compounds that contain
carbon.
There are lots of them.
90% + of known compounds are Organic
Why?
Because carbon forms chains
9. Homologous series
A group of compounds in which there is a
constant increment of change in molecular
structure from one compound in the series
to the next.
The alkanes differ by one CH2 group each
time
CnH2n+2
10. Types of formulas
Molecular formula – C4H10
Complete structural formula
Condensed structural formula – C – H
bonds are understood.
Condensed structural formula – C-H and
C-C bonds understood
Carbon skeleton; hydrogens understood
11. Draw a complete structural formula for the
straight-chained alkane having 3 carbons
12. Branched-chain Alkanes
Substituent – an atom or group of atoms
that can take the place of a hydrogen atom
on a parent hydrocarbon molecule.
Parent chain – the longest carbon chain.
May not always be written in a straight line on
paper.
13.
14.
15. Alkyl group – a hydrocarbon substituent
CH3 – methyl
CH3CH2 – ethyl
CH3CH2CH2 – propyl
Alkyl group = alkane – 1 H
Name = -ane + yl
What would CH3CH2CH2 CH2be called?
17. Naming a branched-chain alkane
1. Find the longest chain of carbons. This
is the parent chain
2. # the carbons on the parent chain.
Starting with the end that will give the
substituents the smallest numbers
3. Add #s to the names of the substituent
groups to identify their positions on the
chain.
18. 4. Use prefixes to indicate if a group appears
more than once.
Di – 2
Tri – 3
Tetra – 4
Penta – 5
5. List the names of the alkyl substituents in
alphabetical order (ignore prefixes when
alphabetizing.)
6. Use proper punctuation
Commas separate #s from #s
Hyphens separate #s from words
19.
20.
21. Properties of alkanes
Nonpolar – electrons are shared about
equally
Very weak van der Walls forces
(dispersion)
Have a low mass, low boiling point
Do not dissolve in water.
Flammable
22. Unsaturated hydrocarbons
Alkenes – hydrocarbons containing carbon-
carbon double covalent bonds
Unsaturated compounds – organic compounds
that contain double or triple C-C bonds
They have fewer than the number possible of H in their
structure.
Saturated hydrocarbons – alkanes – all single
bonds.
Have the maximum number of hydrogens possible.
23. Naming alkenes
1. Find the longest chain in the molecule
THAT CONTAINS the double bond.
(parent)
2. Root name from alkane -ane +ene
3. # the chain so that the double bond
gets the lowest possible #. (# is listed in
the name)
Subsituents named just like alkanes.
24. Naming alkynes
Alkynes – hydrocarbons containing C-C
triple bonds
Named just like alkenes, -yne instead of
–ene
25.
26.
27. Hydrocarbon rings
Cyclic hydrocarbons – compounds that
contain a hydrocarbon ring.
Aliphatic compounds – do not contain
rings
Aromatic compounds – compounds in
which the bonding is like that of benzene.