SiF6 2- Ion and Lewis Structure Concepts

The video tutorial explains the process of drawing the Lewis structure for SiF6 2-. It begins by calculating the total number of valence electrons, considering the contributions from silicon, fluorine, and the negative charge. Silicon, being the least electronegative, is placed at the center with fluorine atoms surrounding it. Chemical bonds are formed between silicon and each fluorine atom, using up some of the valence electrons. The tutorial then covers completing the octets for the fluorine atoms and discusses the concept of an expanded octet for silicon, which is permissible as it is below period 2 on the periodic table. Finally, the structure is completed by adding brackets and indicating the 2- charge to show it is a negative ion.

How many total valence electrons are present in the SiF6 2- ion?

• 60

• 54

• 48

• 32

Which element is placed at the center of the SiF6 2- Lewis structure?

• Silicon

• Oxygen

• Carbon

• Fluorine

How many valence electrons are used to form bonds between silicon and fluorine in SiF6 2-?

• 24

• 18

• 12

• 6

What is the significance of completing the octets for fluorine atoms in the SiF6 2- structure?

• It changes the molecule's charge.

• It decreases the molecule's size.

• It increases the molecule's reactivity.

• It stabilizes the molecule.

Why is silicon allowed to have more than eight valence electrons in the SiF6 2- structure?

• It is highly electronegative.

• It is in period 3 and can have an expanded octet.

• It is a metal.

• It forms ionic bonds.

What is the purpose of adding brackets around the SiF6 2- Lewis structure?

• To indicate it is a molecule.

• To show it is a positive ion.

• To denote it is a negative ion.

• To highlight the central atom.

What charge does the SiF6 2- ion carry?

• Positive one

• Negative one

• Positive two

• Negative two