Match each of the Lewis structures (a to c) with the correct diagram (1 to 3) of its shape, and name the shape; indicate if each molecule is polar or nonpolar. Assume X and Y are nonmetals and all bonds are polar covalent. (6.6, 6.8, 6.9)1.
2.
3.
c.

Verified step by step guidance

1. Identify the Lewis structure given: Y-X3 with a lone pair on X.
2. Determine the electron pair geometry around the central atom X. With three bonded atoms and one lone pair, the geometry is tetrahedral.
3. Determine the molecular shape. With one lone pair, the shape is trigonal pyramidal.
4. Match the molecular shape to the diagrams provided. Diagram I shows a trigonal pyramidal shape.
5. Assess the polarity. The molecule is polar due to the asymmetrical shape and polar covalent bonds.

Key Concepts

Lewis Structures

Lewis structures are diagrams that represent the bonding between atoms in a molecule and the lone pairs of electrons that may exist. They help visualize the arrangement of electrons and the connectivity of atoms, which is crucial for predicting molecular shapes and properties. Understanding how to draw and interpret Lewis structures is essential for analyzing molecular geometry and polarity.

Molecular Geometry

Molecular geometry refers to the three-dimensional arrangement of atoms within a molecule. It is determined by the number of bonding pairs and lone pairs of electrons around the central atom, following the VSEPR (Valence Shell Electron Pair Repulsion) theory. Recognizing the shapes, such as linear, trigonal planar, or tetrahedral, is vital for understanding how molecular structure influences physical and chemical properties, including polarity.

Polarity of Molecules

Polarity in molecules arises from the distribution of electrical charge, which is influenced by the electronegativity of the atoms involved and the molecular geometry. A molecule is polar if it has a net dipole moment due to an uneven distribution of charge, often resulting from polar covalent bonds. Identifying whether a molecule is polar or nonpolar is crucial for predicting its interactions with other substances, such as solubility and reactivity.