Comparing Boiling Points of Methanal & Ethanal

[iluvchem09]

Why is there a difference in boiling points between methanal (CH2O) which is -21degrees Celsius and ethanal (CH3CHO) which is +21degrees Celsius?

 

[Astronuc]

Why is there a difference in boiling points between methanal (CH2O) which is -21degrees Celsius and ethanal (CH3CHO) which is +21degrees Celsius?

I would expect the difference molecular mass has something to do with it.

 

[iluvchem09]

I was researching it, and came up with mass, hydrogen bond with oxygen, and electrostatic attraction between molecules. What do you think would be the #1 reason?

 

[alxm]

Hydrogen bonding. It's by far the strongest of the mentioned effects.

Also, ethanal forms a more stable enolate.