What functional group do alcohols have?
OH group
Polar or non-polar?
Polar O-H bond
Molecules are therefore polar
Strong hydrogen bonds
Physical properties (compared to alkanes)?
Less volatile
Higher melting points
Greater water solubility
Volatility?
When liquid- hydrogen bonds hold the alcohol molecule together
Bonds must be broken to change the liquid alcohol into a gas
Solubility in water?
Can form hydrogen bonds
Combustion?
Co2 + H20
Exothermic reaction
What oxidising agent is used?
K2CR207 and H2S04
Colour change?
Orange -> green
What ions are formed?
Cr2072- -> Cr3+
(Dichromate VI ions) -> chromium (III) ions
What happens when you gently heat and distill a primary alcohol with potassium dichromate?
Forms an aldehyde
Colour change from orange to green
How to form a carboxylic acid?
HUR a primary alcohol
Or HUR an aldehyde
Oxidation of secondary alcohols?
Ketones
HUR
Orange -> green
What is dehydration (elimination)?
The removal of a water molecule
Heat under reflux with a concentrated H2S04/H3PO4
Forms an alkene and water
What is substitution of an alcohol?
React with hydrogen halides to form haloalkanes
HUR with H2SO4 and sodium halide
