# Why are alcohols with longer chains less polar?

In my self-study, I recently came across the following question:

"Choose the solute of each pair that would be more soluble in hexane ($\ce{C6H14}$). Explain your answer.

(a) $\ce{CH3(CH2)10OH}$ or $\ce{CH3(CH2)2OH}$ ..."

Undecanol is more soluble in hexane because it is apparently less polar than propanol. Further Internet searches revealed that alcohols decrease in polarity as the chain length increases (assuming a basis in an alkane; don't know if this rule generalizes which I guess is a sub-question) but it is still not clear why. None of the sources I found explained this. The way I imagine things, the carbon-hydrogen bonds should add a bunch of zero vectors to the the O–H vector that both molecules share, giving the same polarity in both cases. But this is apparently wrong.

So why is undecanol less polar than propanol then? Does it have something to do with a more advanced bonding theory?