Valence Electrons and Lewis Structures

The video tutorial explains how to write the Lewis structure for AlCl4-. It begins by counting the valence electrons of aluminum and chlorine, then calculates the total valence electrons for the ion. The tutorial proceeds to place aluminum at the center and chlorine atoms around it, forming bonds and ensuring each atom has a complete octet. Finally, the structure is enclosed in brackets with a negative sign to indicate it is an ion.

What is the first step in writing the Lewis structure for AlCl4-?

• Calculate the formal charge

• Identify the hybridization

• Count the valence electrons

• Determine the molecular geometry

How many valence electrons does aluminum contribute to the AlCl4- structure?

• 1

• 2

• 4

• 3

What is the total number of valence electrons in AlCl4-?

• 28

• 30

• 32

• 34

Which atom is placed at the center of the AlCl4- Lewis structure?

• Chlorine

• Oxygen

• Aluminum

• Hydrogen

How many electrons are initially used to form bonds between aluminum and chlorine atoms?

• 6

• 4

• 10

• 8

What is the purpose of completing the octets for chlorine atoms in the structure?

• To reduce the number of valence electrons

• To stabilize the molecule

• To increase the molecular weight

• To change the molecular shape

How many total valence electrons are used in the final AlCl4- structure?

• 34

• 32

• 30

• 28

What notation is used to indicate that AlCl4- is an ion?

• A positive sign

• Brackets with a negative sign

• A double bond

• Asterisks

What is the significance of placing a negative sign outside the brackets in the Lewis structure?

• It shows the molecule is neutral

• It denotes a double bond

• It indicates a positive charge

• It signifies the presence of an extra electron