Ch.10 - Molecular Shapes & Valence Bond TheoryWorksheetSee all chapters
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Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Solution: Carbon monoxide, CO, is isoelectronic to N2.Assume that the diagram in the first figure that described NO can also be used to describe the MOs of CO. What is the predicted bond order for CO?

Problem

Carbon monoxide, CO, is isoelectronic to N2.

Assume that the diagram in the first figure that described NO can also be used to describe the MOs of CO.

What is the predicted bond order for CO? The diagram shows an N atom and an O atom, each with two electrons in their 2s orbital (the N atom is at a higher energy). The N atom has three electrons in its 2p orbitals while the O atom has four (the N atom is at a higher energy). For the 2s orbitals, the higher energy antibonding MO (sigma asterisk 2s) is occupied, as is the lower energy bonding molecule orbital (sigma 2s). For the 2p orbitals, the highest energy antibonding (sigma asterisk 2p) is vacant, the second highest energy antibonding two orbitals, pi asterisk 2p, have one electron, the second lowest energy bonding orbital, pi 2p, is full with four electrons, and the lowest energy bonding molecule orbital is full (sigma 2p).