CNO- Lewis Structure and Valence Electrons

The video tutorial explains the Lewis structure for CNO-. It begins by identifying the total valence electrons and arranging the atoms with carbon at the center. The tutorial demonstrates how to share electrons to form bonds and complete octets, resulting in a valid Lewis structure. The video also discusses alternative structures and explains why the chosen structure is optimal due to formal charges, with oxygen having a negative charge that matches the overall charge of the ion.

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

• 20

• 14

• 16

• 18

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

• Carbon

• Oxygen

• Hydrogen

• Nitrogen

What is the initial number of valence electrons around Carbon before sharing with Nitrogen?

• 8

• 2

• 4

• 6

How many valence electrons does Nitrogen have after sharing with Carbon to form a triple bond?

• 8

• 7

• 6

• 9

Why is a triple bond formed between Carbon and Nitrogen in the CNO- structure?

• To increase the number of valence electrons

• To make the structure symmetrical

• To satisfy the octet rule for Carbon

• To decrease the formal charge on Oxygen

What is the formal charge on Oxygen in the CNO- Lewis structure?

• 0

• -1

• +1

• -2

What would be the result of forming a double bond between Carbon and Oxygen?

• The octet rule would not be satisfied for Carbon

• The structure would have a negative charge

• All atoms would have a formal charge of 0

• Oxygen would have a positive formal charge

Why is the arrangement with a triple bond between Carbon and Nitrogen preferred?

• It gives each atom a formal charge of 0

• It aligns with the electronegativity of the atoms

• It results in the lowest energy state

• It maximizes the number of bonds