CIA Problem 4.2 Draw the Lewis dot structures for the molecules CO and NO. What is different about these structures compared with the general examples we have seen so far? How could these Lewis structures provide insight into the high chemical reactivity of these molecules?

Verified step by step guidance

1. Identify the total number of valence electrons for each molecule. For CO, carbon has 4 valence electrons and oxygen has 6, totaling 10 valence electrons. For NO, nitrogen has 5 valence electrons and oxygen has 6, totaling 11 valence electrons.
2. Draw the skeletal structure of each molecule. For CO, place carbon and oxygen next to each other. For NO, place nitrogen and oxygen next to each other.
3. Distribute the valence electrons around the atoms to satisfy the octet rule as much as possible. Start by placing electrons between the atoms to form bonds, then distribute the remaining electrons to complete the octets.
4. For CO, you will find that a triple bond between carbon and oxygen is necessary to satisfy the octet rule for both atoms. For NO, achieving a full octet for both atoms is not possible due to the odd number of electrons, resulting in a double bond with one unpaired electron.
5. Discuss the implications of these structures: The presence of a triple bond in CO and an unpaired electron in NO contributes to their high reactivity. The triple bond in CO makes it a strong bond, but the molecule is still reactive due to the polarity and potential for bond formation. The unpaired electron in NO makes it a radical, which is highly reactive.

Key Concepts

Lewis Dot Structures

Lewis dot structures are diagrams that represent the valence electrons of atoms within a molecule. They illustrate how electrons are shared or transferred between atoms to form bonds, using dots to signify valence electrons and lines for covalent bonds. Understanding these structures is crucial for predicting molecular geometry and reactivity.

Molecular Reactivity

Molecular reactivity refers to how likely a molecule is to undergo a chemical reaction. Factors influencing reactivity include the presence of lone pairs, bond strength, and the overall electron configuration. Molecules like CO and NO exhibit high reactivity due to their unique electron arrangements and the presence of multiple bonds, which can facilitate reactions.

Formal Charge

Formal charge is a concept used to determine the distribution of electrons in a molecule and assess the stability of its Lewis structure. It is calculated by comparing the number of valence electrons in the free atom to the number of electrons assigned in the Lewis structure. A lower formal charge on atoms typically indicates a more stable structure, which is particularly relevant for understanding the reactivity of CO and NO.