Lewis Structures and Valence Electrons

This video tutorial explains how to draw the Lewis structure for the borate ion (BO3 3-). It begins by counting the total valence electrons, considering the contributions from boron and oxygen atoms, and the additional electrons due to the negative charge. The tutorial then guides viewers through placing the least electronegative atom, boron, at the center, and arranging oxygen atoms around it. It demonstrates how to form chemical bonds by pairing electrons between atoms and completing the octets for the oxygen atoms. The video highlights that boron is an exception to the octet rule, being stable with only six valence electrons. The tutorial concludes with the finalized Lewis structure for the borate ion.

How many total valence electrons are present in the borate ion BO3 3-?

• 27

• 24

• 21

• 18

Which atom is placed at the center of the Lewis structure for BO3 3-?

• Carbon

• Oxygen

• Boron

• Hydrogen

What is the purpose of placing pairs of electrons between atoms in a Lewis structure?

• To indicate the charge

• To show the chemical bond

• To represent lone pairs

• To balance the equation

How many valence electrons does each oxygen atom have in the completed Lewis structure?

• 9

• 8

• 7

• 6

Why is boron an exception to the octet rule in the borate ion?

• It forms a double bond with oxygen

• It shares electrons with hydrogen

• It is stable with 6 valence electrons

• It can only hold 4 electrons

What is the total number of valence electrons used in the Lewis structure of BO3 3-?

• 18

• 24

• 20

• 22

What is the charge on the borate ion BO3 3-?

• 2-

• 4-

• 1-

• 3-