Butan-1-ol has a boiling point of approx. 117.7 celsius, and Butan-2-ol has a boiling point of approx. 99.5 celsius. What causes this difference in boiling points?
My initial idea would be that Butan-2-ol essentially has a side-branch (the OH-group), whereas Butan-1-ol does not. This should disrupt the London dispersion forces and thereby reduce the strength. Another idea would be that the position of the OH-group being in the middle for Butan-2-ol creates fewer Hydrogen bonds than Butan-1-ol does. My third idea is that the position reduces the strength of the regular dipole-dipole bonds (when I mean regular I mean not hydrogen bonds), because the polarisation is weakened.
Am I correct in any of my assumptions? Is there something else to it?