Hydrocarbons
What elements are hydrocarbons made of?
Carbon and hydrogen.
What is the functional group present in all alcohols?
Hydroxyl group (–OH).
What suffix is used for naming aldehydes?
“–al.”
What suffix is used for naming ketones?
“–one.”
What is the general formula for alkanes?
CₙH₂ₙ₊₂
What do we call hydrocarbons with at least one triple bond between carbons?
Alkynes.
How does an alcohol differ from the corresponding alkane?
One hydrogen atom is replaced by an –OH group.
What is the molecular formula for ethanal?
C₂H₄O.
What is the name of the ketone with three carbon atoms?
Propanone (acetone).
What is the molecular formula for methane?
CH₄
What do we call hydrocarbons that contain double or triple bonds?
Unsaturated hydrocarbons.
Why are small alcohols soluble in water?
Because the –OH group forms hydrogen bonds with water molecules.
How can you tell the difference between an aldehyde and a ketone just by the structure?
In aldehydes, the C=O group is at the end of the chain; in ketones, it’s in the middle.
What is the name of the ketone with five carbon atoms?
Pentanone.
What is the molecular formula for ethyne?
C₂H₂
What does the prefix “sept–” tell us about a hydrocarbon?
It has 7 carbon atoms
What is the molecular formula for ethanol?
C₂H₅OH
What functional group identifies an aldehyde?
A carbonyl group (C=O) at the end of the chain.
Why are ketones often used as solvents?
They are polar enough to dissolve many organic compounds but still mix with nonpolar substances.
What is the general formula for alkynes?
CₙH₂ₙ₋₂
What is the name of the hydrocarbon with four carbons and a double bond?
Butene.
Explain why alcohols generally have higher boiling points than alkanes.
Hydrogen bonding between –OH groups increases the strength of intermolecular forces.
Why do aldehydes generally have higher boiling points than alkanes of similar mass?
The polar C=O group increases dipole–dipole interactions.
Predict the structural difference between pentanone and pentanal.
Pentanone has the C=O in the middle; pentanal has it at the end.
Name the hydrocarbon with the formula C₄H₈.
Butene