How does one apply the knowledge of the direction of a molecular dipole moment? I was watching Khan academy's video about molecular dipole moments, which explained what they are and how they can be calculated. I also read this article. 

Both sources explain the concept similar to common organic chemistry textbooks, but they did not provide any information regarding the uses or applications of a molecular dipole's direction, nor did the google search I conducted later.

So far, two things are clear to me:


A dipole moment is a vector, and therefore has a quantity and a direction.
Larger dipole moment is associated with a more polar molecule. This a good enough reason to find out how large is the dipole moment.


My question is: What possible applications can knowing the direction of a molecular dipole moment have?
Take a look at chemlibretexts. I'll just write an overview.



A dipole is a vector representing the charge distribution in a molecule. It's drawn from the positive-density charge side towards the negative. 

Some examples


Phase change 


How do we explain $\ce{CO2}$ fusion temperature is $-78\,^\circ$C while $\ce{SO2}$ is $-10\,^\circ$C? Because of its dipole magnitude. In the first one, there's no net dipole, but there is for the second one. 

The bigger molecular interactions the more they oppose to temperature-increasings. 


Solubility is higher for alcohols than lipids* in water. Again dipole-dipole interaction is stronger (energetically more favourable) than dipole-induced dipole interaction. 
CO$_2$ has no electric dipole in the symmetric vibration. According to quantum mechanics, if electric dipole does not change when it absorbes light of a specific energy, it will not be susceptible of a infrared measure. This particular vibrational mode will be (and it is) infrared inactive.