1.4 Alcohols, Ethers, and Thiols Flashcards
Alcohol definition
Organic compound that contains
the hydroxyl (–OH) functional group
Primary alcohol definition
An alcohol in which the hydroxyl group is bonded to a terminal carbon atom
Secondary alcohol definition
An alcohol in which the hydroxyl group is bonded to a carbon atom with two alkyl groups bonded to it
Tertiary alcohol definition
An alcohol in which the hydroxyl group is bonded to a carbon atom with three alkyl groups bonded to it
Why are alcohols considered polar molecules?
The presence of the electronegative oxygen atom in the –OH group affects the polarity of the molecule.
The C–O bond is significantly more polar than the C–H bond based on the ΔEN difference between carbon and oxygen compared to that between carbon and hydrogen.
The bond between oxygen and hydrogen is
also polar.
Alcohols containing more than one –OH group are referred to as _________.
The suffix -diol (for ____ –OH groups) or -triol (for ____ –OH groups) is added to the
alkane name instead of -ol.
polyalcohols; 2; 3
What is the name of the simplest aromatic alcohol that’s made up of a benzene ring with one hydroxyl group bonded to it?
Phenol
hydrogen bonding
A strong dipole–dipole force between a hydrogen atom attached to a highly electronegative atom
(N, O, or F) in one molecule and a highly
electronegative atom in another molecule
Dehydration reaction
A reaction that involves the removal of a hydrogen atom and a hydroxyl group from the reactant, producing a slightly smaller molecule and water
Ether definition
An organic compound containing an oxygen atom between 2 carbon atoms in a chain
Condensation reaction
A chemical reaction in which two molecules combine to form a larger molecule and a small
molecule, such as water
Thiol definition
An organic compound that contains the sulfhydryl (–SH) group
Alcohols contain a hydroxyl group, -___. The hydroxyl group allows alcohols to form ________ bonds.
OH; hydrogen
True or false:
Because the hydrocarbon region of an alcohol molecule is non-polar, alcohols tend to be able to dissolve both polar and non-polar substances.
True
If you were given two samples and told that one was ethanol and one was heptan-2-ol, describe 2 tests that you could run on the samples to identify them.
Ethanol is a primary alcohol with a short carbon
chain.
Heptan-2-ol is a secondary alcohol with a longer carbon chain. Since simple alcohols with short carbon chains are more soluble in water than those with longer carbon chains, a solubility test can be used to identify the two compounds.
Another test is to perform a dehydration rxn using sulfuric acid as a catalyst on each alcohol to change it to an alkene.
The dehydration of ethanol, which is a primary
alcohol, will produce only one alkene—ethene.
For the dehydration of heptan-2-ol, which
is a secondary alcohol, a mixture of two different alkenes—heptenes—will be produced.
