C14 - Alcohols Flashcards
What is the functional group of an alcohol?
-OH (hydroxyl group)
What is the general formula of an alcohol
CnH2n+1OH
How do you name an alcohol
1) Suffix is -ol (number before ol)
2) Identify longest carbon chain
4) Identify and number any alkyl groups
What are the physical properties of alcohols compared to alkanes?
-Less volatile
-Higher melting and boiling points
-Greater solubility
Do the differences between alcohols and their corresponding alkane increase or decrease as the chain length increases?
Decrease
Why does the difference between alcohols and alkanes decrease?
-OH group becomes relatively smaller
Why do alcohols have higher boiling points than alkanes?
-Alkanes have non-polar bonds and are therefore non-polar
-Intermolecular forces between non-polar molecules are weak London forces
-Alcohols have a polar O-H bond, therefore, they are polar molecules
-Intermolecular forces will be weak London forces and string hydrogen bonds
How do you draw a hydrogen bond
What is a hydrogen bond?
Strong dipole-dipole attraction between an electron deficient hydrogen atom on a highly electronegative atom containing N/O/F
What is volatility?
Ease at which a liquid turns into a gas
Increases with boiling point
What is the difference in volatility of alkanes and alcohols?
Hydrogen bond requires more energy to overcome than weak London forces
Alcohols have lower volatility
Why are alcohols soluble in water
Polar OH group forms hydrogen bonds with water
What happens to solubility of alcohols as chain length increases?
Decreases
What can alcohols be classified as?
Primary
Secondary
Tertiary
What is a primary alcohol?
Alcohol in which the OH group is attached to a carbon atom that is attached to two or hydrogen atoms (one alkyl group)