Textbook Question
Consider the Lewis structure shown below.
(a) Does the Lewis structure depict a neutral molecule or an ion? If it is an ion, what is the charge on the ion? What is the charge on the ion
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Ch.9 - Molecular Geometry and Bonding Theories
Chapter 9, Problem 69
(a) What is the difference between hybrid orbitals and molecular orbitals? (b) How many electrons can be placed into each molecular orbital (MO) of a molecule? (c) Can antibonding molecular orbitals have electrons in them?
Verified step by step guidance1
Step 1: Understand the concept of hybrid orbitals. Hybrid orbitals are formed by the combination of atomic orbitals within a single atom. This process is called hybridization, and it helps explain the geometry of molecular bonding. For example, in methane (CH₄), the carbon atom undergoes sp³ hybridization to form four equivalent hybrid orbitals.
Step 2: Understand the concept of molecular orbitals. Molecular orbitals (MOs) are formed by the combination of atomic orbitals from different atoms in a molecule. These orbitals belong to the entire molecule rather than a single atom. MOs can be bonding, antibonding, or non-bonding, depending on the phase relationship of the combining atomic orbitals.
Step 3: Determine how many electrons can be placed into each molecular orbital. According to the Pauli Exclusion Principle, each molecular orbital can hold a maximum of two electrons with opposite spins.
Step 4: Explore whether antibonding molecular orbitals can have electrons. Antibonding molecular orbitals, denoted as σ* or π*, can indeed have electrons. However, electrons in these orbitals can weaken or destabilize the bond between atoms because they are higher in energy compared to bonding orbitals.
Step 5: Summarize the key differences and properties. Hybrid orbitals are localized on a single atom and explain molecular geometry, while molecular orbitals are delocalized over the entire molecule and explain bonding interactions. Each MO can hold two electrons, and antibonding MOs can contain electrons, affecting the stability of the molecule.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Hybrid Orbitals
Hybrid orbitals are formed by the combination of atomic orbitals from the same atom to create new orbitals that are degenerate in energy and oriented to minimize electron repulsion. This concept is crucial for understanding molecular geometry and bonding in covalent compounds, as hybridization allows for the formation of bonds with specific angles, such as in sp3, sp2, and sp hybridizations.
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00:51
Hybridization
Molecular Orbitals
Molecular orbitals (MOs) are formed by the linear combination of atomic orbitals (LCAO) from different atoms in a molecule. These orbitals can be bonding, antibonding, or non-bonding, and they describe the distribution of electrons in a molecule. Understanding MOs is essential for predicting the stability and reactivity of molecules, as well as their electronic properties.
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Electron Capacity of Molecular Orbitals
Each molecular orbital can hold a maximum of two electrons with opposite spins, according to the Pauli exclusion principle. The filling of MOs follows Hund's rule and the Aufbau principle, which dictate that electrons occupy the lowest energy orbitals first before pairing up. This concept is vital for determining the electron configuration of molecules and understanding their chemical behavior.
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Related Practice
Textbook Question
Predict the molecular geometry of each of the following molecules: (b) H O C O C O O H
Textbook Question
What hybridization do you expect for the atom that is underlined in each of the following species? (a) IO2- (b) NH4+ (c) SCN- (d) BrCl3
Textbook Question
(a) If you combine two atomic orbitals on two different atomsto make a new orbital, is this a hybrid orbital or a molecularorbital?
Textbook Question
(b) If you combine two atomic orbitals on one atom to make a new orbital, is this a hybrid orbital or a molecular orbital?
Textbook Question
Consider the H2+ ion. (a) Sketch the molecular orbitals of the ion and draw its energy-level diagram.