Alcohols Flashcards
(16 cards)
What is the functional group of alcohols?
The hydroxyl group, written as -OH
What is the general formula for an alcohol?
Cn H2n+1 OH
What is the IUPAC suffix used for naming alcohols?
-ol
What prefix is used for the -OH group when other functional groups are present?
Hydroxy-
How do you name alcohols with more than one -OH group?
Use prefixes di-, tri-,tetra- and indicate positions
What is the shape around the oxygen atom in an alcohol molecule?
A bent or angualr shape due to two bonding pairs and two lone pairs
What is the approximate bond angle in the C-O-H group of alcohols?
About 105*
Why is the C-O-H bond angle in alcohols less than the tetrahedral angle of 109.5*?
This is because lone pairs repel mor estrongly than bonding pairs, reducing the angle
How many lone pairs are ont he oxygen atom in an alcohol molecule?
Two lone pairs
What is a primary alcohol?
An alcohol where the carbon bonded to the -OH group is attached to one R group and two hydrogen atoms
How are alcohols classified?
As primary (1), secondary (2), or tertiary (3*) based on the number of alkyl groups (R groups) attached to the carbon with the -OH group
What is a secondary alcohol?
An alcohol where the carbon bonded to the -OH group is attached to two R groups and one hydrogen atom
What is a tertiary alcohol?
An alcohol where the carbon bonded to the -OH group is attached to three R groups and no hydrogen atoms
Why do alcohols have higher boiling points than alkanes of similar Mr?
This is because alcohols form hydrogen bonds between molecules due to the -OH group
Why are short chain alcohols soluble in water?
This is because the -OH group can form hydrogen bonds with water, and this effect dominates over the hydrocarbon chain
Why are long - chain alcohols less soluble in water?
This is because the non - polar hydrocarbon chain dominates, reducing the effect of hydrogen bonding with water
