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AS Chemistry Multiple choice question help TQ

Which compound has the highest boiling point?

A. Butanal
B. Butan-2-ol
C. But-2-ene
D. 1-fluorobutane
Reply 1
Butan-2-ol cuz it has hydrogen bonding, the rest only have weaker intermolecular forces
Thank you!!!
Original post by aaaronaa
butan-2-ol cuz it has hydrogen bonding, the rest only have weaker intermolecular forces
Original post by aaaronaa
Butan-2-ol cuz it has hydrogen bonding, the rest only have weaker intermolecular forces

Thats correct tho 1-fluorobutane has a permanent dipole
Reply 4
That is incorrect. Butanal has a higher boiling point than butan-2-ol, this is because butanal has a larger surface area as it is not branched unlike butan-2-ol l. Due to having a larger surface area, it has more contact points which increases the strength of van der waals forces.
Original post by N.R.A
That is incorrect. Butanal has a higher boiling point than butan-2-ol, this is because butanal has a larger surface area as it is not branched unlike butan-2-ol l. Due to having a larger surface area, it has more contact points which increases the strength of van der waals forces.

butan-2-ol is able to form hydrogen bonds unlike butanal which are the strongest intermolecular forces, must stronger than van der waals forces. Therefore, the boiling point of butan-2-ol is higher. they also have very similar surface areas.
Original post by leonnicholl
butan-2-ol is able to form hydrogen bonds unlike butanal which are the strongest intermolecular forces, must stronger than van der waals forces. Therefore, the boiling point of butan-2-ol is higher. they also have very similar surface areas.
Why can't 1-fluorobutane and butanal form hydrogen bonds as they also contain F and O atoms?
Reply 7
Original post by lanadelslay1989
Why can't 1-fluorobutane and butanal form hydrogen bonds as they also contain F and O atoms?
Hydrogen bond occurs between lone pairs of electronegative atoms such as N, O, F and a hydrogen atom in a N-H, O-H, or F-H bond so yes, you're correct, F and O atoms can indeed form hydrogen bonds but cannot in this case as they have no lone pairs available to do so because all their outer electrons are involved in bonding to their different C atoms

While O atom in butan-2-ol has 2 lone pairs available so can involve in hydrogen bonding
Original post by Emmaclems
Hydrogen bond occurs between lone pairs of electronegative atoms such as N, O, F and a hydrogen atom in a N-H, O-H, or F-H bond so yes, you're correct, F and O atoms can indeed form hydrogen bonds but cannot in this case as they have no lone pairs available to do so because all their outer electrons are involved in bonding to their different C atoms
While O atom in butan-2-ol has 2 lone pairs available so can involve in hydrogen bonding

Thank you very much! That makes so much sense.

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