What are the formal charges on boron and fluorine in the following structure?

Question

Quizplus · Accepted Answer

In the given structure, each fluorine atom has 7 valence electrons and is connected to boron which has 3 valence electrons. The octet rule states that each atom should have 8 electrons in its valence shell to achieve stability. Boron in this structure has only 6 electrons in its valence shell which indicates that it is electron deficient or has a positive formal charge. Each fluorine atom in the structure has one lone pair of electrons and is connected to only one boron atom. Thus, fluorine should have a negative formal charge to compensate for the positive formal charge on boron. 
Therefore, the formal charges on boron and fluorine in the given structure are B = 1-, F = 1+. 
Option D correctly shows the formal charges on boron and fluorine as B = 1- and F = 1+.

What Are the Formal Charges on Boron and Fluorine in the Following