Lewis Structures and Formal Charges

The video tutorial explains how to draw the Lewis structure for the BO2- ion. It begins by counting the valence electrons, placing the least electronegative element (boron) in the center, and arranging the oxygen atoms around it. The tutorial covers forming bonds, completing octets, and checking formal charges to ensure the structure is correct. It evaluates different possible structures and concludes with the best Lewis structure, emphasizing the importance of formal charges and the placement of the negative charge on the more electronegative element, oxygen.

What is the total number of valence electrons in the BO2- ion?

• 16

• 14

• 20

• 18

Which element is placed at the center of the BO2- Lewis structure?

• Oxygen

• Hydrogen

• Boron

• Carbon

What is the total number of valence electrons used in forming bonds in the initial Lewis structure?

• 2

• 4

• 6

• 8

How many valence electrons are initially placed between boron and each oxygen in the BO2- structure?

• 4

• 3

• 2

• 1

How many valence electrons does boron typically need to be stable?

• 4

• 6

• 8

• 10

What is the formal charge on the oxygen atom in the best Lewis structure of BO2-?

• +1

• -1

• 0

• -2

What happens to the formal charge of boron if two double bonds are formed in BO2-?

• It becomes -2

• It remains 0

• It becomes -1

• It becomes +1

What is the formal charge on boron in the best Lewis structure of BO2-?

• -2

• 0

• -1

• +1

Why is the negative formal charge preferred on the oxygen atom in BO2-?

• Oxygen is more electronegative

• Boron is less electronegative

• Boron is more electronegative

• Oxygen is less electronegative

What is the significance of placing brackets around the Lewis structure of BO2-?

• To indicate it is a molecule

• To show it is an ion

• To highlight the central atom

• To denote resonance