What are the electron-domain and molecular geometries of a molecule that has the following electron domains on its central atom? (a) Three bonding domains and no nonbonding domains (b) Three bonding domains and one nonbonding domain (c) Two bonding domains and two nonbonding domains.

Verified step by step guidance

1. Step 1: Understand the concept of electron-domain geometry, which considers both bonding and nonbonding electron pairs around the central atom to determine the overall shape.
2. Step 2: For part (a), identify the electron-domain geometry for a molecule with three bonding domains and no nonbonding domains. This corresponds to a trigonal planar geometry.
3. Step 3: For part (a), since there are no nonbonding domains, the molecular geometry is the same as the electron-domain geometry, which is trigonal planar.
4. Step 4: For part (b), identify the electron-domain geometry for a molecule with three bonding domains and one nonbonding domain. This corresponds to a tetrahedral electron-domain geometry.
5. Step 5: For part (b), determine the molecular geometry by considering the effect of the nonbonding domain, which results in a trigonal pyramidal molecular geometry.

Key Concepts

Electron-Domain Geometry

Electron-domain geometry refers to the spatial arrangement of all electron domains (bonding and nonbonding) around a central atom in a molecule. It is determined by the number of electron domains, which can include single bonds, double bonds, triple bonds, and lone pairs. The geometry helps predict the overall shape of the molecule based on the repulsion between these electron domains.

Molecular Geometry

Molecular geometry describes the three-dimensional arrangement of the atoms in a molecule, considering only the positions of the nuclei of the atoms. It is influenced by the electron-domain geometry but differs in that it does not account for lone pairs when determining the shape. Understanding molecular geometry is crucial for predicting the physical and chemical properties of the molecule.

VSEPR Theory

Valence Shell Electron Pair Repulsion (VSEPR) theory is a model used to predict the geometry of molecules based on the repulsion between electron pairs surrounding a central atom. According to VSEPR, electron pairs will arrange themselves to minimize repulsion, leading to specific shapes such as trigonal planar, tetrahedral, or bent. This theory is fundamental for determining both electron-domain and molecular geometries.