Lewis Structures and Valence Electrons

Dr. B explains how to draw the Lewis structure for CH2O, also known as methanal or formaldehyde. The process begins with calculating the total valence electrons using the periodic table. Carbon, hydrogen, and oxygen's valence electrons are summed to get 12. The structure is built by placing carbon in the center, hydrogen on the outside, and oxygen at the top. Initial bonds are formed, and adjustments are made to satisfy the octet rule. The final structure is presented with a double bond between carbon and oxygen, ensuring all atoms have complete valence shells.

What is the chemical formula for methanal?

• C2H4

• CH4

• CH2O

• C2H6

How many total valence electrons are present in CH2O?

• 16

• 14

• 12

• 10

Which atom is placed at the center of the Lewis structure for CH2O?

• Oxygen

• Carbon

• Hydrogen

• Nitrogen

How many valence electrons does Carbon contribute in CH2O?

• 6

• 4

• 8

• 2

What is the total number of bonds formed in the Lewis structure of CH2O?

• 5

• 4

• 3

• 2

How many electrons does each Hydrogen atom need to be stable?

• 8

• 2

• 1

• 4

What type of bond is formed between Carbon and Oxygen in CH2O?

• Single bond

• Ionic bond

• Double bond

• Triple bond

How many electrons does Oxygen need to complete its octet in CH2O?

• 8

• 2

• 4

• 6

What does the double line between Carbon and Oxygen represent in the structural formula?

• Double bond

• Triple bond

• Single bond

• No bond