Section B Flashcards
What is an alcohol?
A homologous series similar to alkanes but with one hydrogen replaced by a hydroxyl functional group (OH)
What is a primary alcohol?
An alcohol where the carbon bonded to the hydroxyl group is bonded to one other carbon atom
What is a secondary alcohol?
An alcohol where the carbon bonded to the hydroxyl group I bonded to two other carbons
What is a tertiary alcohol?
An alcohol where the carbon bonded to the hydroxyl group is bonded to three other carbon atoms
What is a diol?
A homologous series similar to alcohols but with two hydroxyl functional groups
What is a triol?
A homologous series similar to alcohols but with three hydroxyl functional groups
What forces act on alcohols?
Hydrogen bonding
How is the melting point and boiling point of alcohols?
They have high melting/boiling points due to hydrogen bonding meaning more energy is required to deprecate molecules
How does the melting point and boiling point differ between long and short chain alcohols?
Boiling/melting point will be less for long chain alcohols than shorter because in short chain alcohols it is likely the dipoles will be close enough to interact and a long chain may not have close enough molecules to form a hydrogen bond
How viscous is an alcohol?
They are more viscous than a molecule with a similar number of electrons because the molecules in an alcohol are held together strongly so they cannot move relative to each other
How does viscosity of alcohols differ with long and short chain alcohols?
Since hydrogen binding is greater in short chain alcohols these are more viscous because the molecules cannot move relative to one another
How are alcohols soluble/miscible with water?
Alcohols can form hydrogen bonds itv water and this makes them soluble/miscible with water
How does physical properties differ between idols and triols?
The more hydroxyl groups in the molecule the more hydrogen bonds the molecule can form so physical properties are higher (melting/boiling point, viscosity, solubility/miscibility)
How must you answer a question on physical properties of alcohols, diols or triols?
- types of bonding present between molecules
- how these types of bonding occur
- comparison of strength of bonds
- explanation of how the strength has the effect of the physical propertie
