1. Chains and rings Basic concepts You need notes on;
Explain each type of formula and give examples for each using hexane and pentene (for molecular, general, structural, displayed, skeletal, 3-D, empirical)
Know the stem name for chains with 1-10 and 20 carbons.

2. Chains and rings Types of functional groups Alkanes Alkenes Arenes
Alcohols
Halogenoalkanes
Carboxylic acids
Esters
Aldehydes
Ketones
Amines

3. Types of formula
Many different types of formula are used within chains and rings dependent on what you are trying to show.
Each has its own use and you must be able to write any compound in any of the formats stated.
For the purpose of showing each formula we will be looking at the alkane propane, C3H8.

4. Types of formula
This shows the number of each atom in the molecule. It can be found from empirical formula and molecular mass.
Molecular formula C3H8
This shows a ratio of the elements within the compound for a homologous series
General formula CnH2n+2
Displayed formula
This shows every atom and every bond in
the molecule; - is single bond; = a double

5. Types of formula
This is a shorthand form of the displayed formula. Written without showing the bonds
Structural formula
CH3CH2CH3
This shows only the carbon skeleton as straight lines, each of which represents C-C bond, plus any functional groups.
Skeletal formula
3-dimensional
This gives the best representation of the shape of a molecule
Empirical C3H8
Simplest ratio of the atoms

6. Types of formula Do the same now for the ALKENE, propene
1) Molecular C3H6
2) General CnH2n
3) Displayed
4) Structural CH2CHCH3
5) Skeletal
6) 3-Dimensional
7) Empirical CH2

7. Types of formula
You must also be able to name various length carbon chains, the following needs to be learnt.
1 carbon = meth
7 carbons = hep
2 carbons = eth
8 carbons = oct
3 carbons = prop
9 carbons = non
4 carbons = but
10 carbons = dec
5 carbons = pent
20 carbons = eicos
6 carbons = hex