Alcohols have a general formula CnH2n+1OH
They are either Primary, Secondary or Tertiary.
To determine which of these the alcohol is, look at whic Carbon the OH group is bonded to.
If bonded to:
- The first Carbon, it is Primary.
- The Second Carbon, it is Secondary.
- The Third Carbon, it is Tertiary.
Hydrogen bonds in alcohols
The OH group in alcohols is polar, this means that it can form hydrogen bonds.
Because the hydrogen bonding is the strongest type of intermolecular force, it gives alcohols a high bioling point.
Alcohols have a relatively low volatility.
Volatility is the tendency of something to evaporate into a gas.
There are 2 ways to make ethanol:
1. Hydration of ethene
- Requires a H3PO4 catalyst
2. Fermentation of glucose - exothermic
- Warm - 30'C - 40'C
- anareobic conditions
- at 15% ethanol, the yeast dies
- Fractional distilation is used to increase conc of ethanol
- low tech
- stll has to be purified
Uses of alcohols
- Alcoholic drinks
- Solvents - Methylated spirits - Ethanol +methanol +purple dye - UNDRINKABLE
- Unleaded petrol
Alcohols can form alkenes
C2H5OH ---->CH2=CH2 +H2O
- Acid catalyst - CONC H2SO4 OR CONC H3PO4
CARBOXYLIC ACID + ETHANOL
PRODUCES ANN ESTHER!!
- warm ethanol with a carboxylic acid and a strong acid catalyst
- forms an esther
- OH bond is broken by a esterification reaction.
ethanol + ethanoic acid ----------------------------->ethyl ethanoate
strong acid catalyst