Alcohols Flashcards
Solubility
Soluble; able to form H-bonds between water molecules
Larger carbon chains are less soluble and their hydrophobic chain is longer
Types of alcohol
Primary; C-OH bonded to 1 C
Secondary; C-OH bonded to 2 C
Tertiary; C-OH bonded to 3 C
How can alcohols be created
Alkanes + steam
Hydrolysis (electrophilic addition)
Phosphoric acid catalyst
Hydrogen bonding
H is bonded to electronegative O
Forms strong intermolecular H-bonds
Alcohol to alkene (3)
- Elimination(dehydration)
- H3PO4 catalyst
- Under reflux
Primary alcohol to aldehyde (3)
- Oxidation
- H3PO4 and acidified potassium dichromate
- Distillation
Primary alcohol to carboxylic acid (3)
- Oxidation
- H3PO4 and acidified potassium dichromate
- Under reflux
Aldehyde to Carboxylic acid (4)
- Oxidation
- H3PO4 and acidified potassium dichromate
- Under reflux
- No water produced
Secondary alcohol to ketone. (3)
- Oxidation
- H3PO4 and acidified potassium dichromate
- reflux
How are ketones formed?
Oxidising secondary alcohol
Product of oxidising tertiary alcohol?
They cannot be oxidised therefore no product.
Why are alcohols very soluble?
- Contain OH group which is able to form H-Bonds with water molecules
Why do alcohols have higher boiling points that alkanes and alkenes? (3)
- Have H-bonds between molecules
- H-bonds are stronger than london forces in alkanes and alkenes
- therefore need more energy to overcome.
Describe the physical properties of alcohols.
- Contains polar O-H bonds due to the difference in electronegativity between the two atoms.
- London forces also present but H-bonds are much stronger between molecules.
- Also less volatile than alkane due to strong H-bonds.
Describe the factor(s) that affect the solubility of alcohols. (2)
- The length of the hydrocarbon chain: the longer the chain, the less influential the O-H bonds become in the molecule’s solubility.
- The hydrocarbon chain consists of non-polar C-C and C-H bonds
