Determine whether each molecule is polar or nonpolar. a. SCl₂ b. SCl₄

Verified step by step guidance

1. Determine the molecular geometry of SCl₄ using the VSEPR theory. Start by counting the number of valence electrons in the sulfur (S) atom and each of the chlorine (Cl) atoms.
2. Arrange the electron pairs around the central sulfur atom to minimize repulsion, considering both bonding pairs (with chlorine atoms) and lone pairs on the sulfur atom.
3. Identify the molecular geometry based on the arrangement of the electron pairs. For SCl₄, the geometry can be predicted as seesaw due to the presence of one lone pair and four bonding pairs around the sulfur atom.
4. Analyze the electronegativity differences between sulfur and chlorine to determine if the S-Cl bonds are polar.
5. Assess the overall molecular polarity based on the molecular geometry and the distribution of the polar bonds. In a seesaw geometry, the asymmetry in the molecule leads to a non-uniform distribution of charge, resulting in a polar molecule.

Key Concepts

Molecular Geometry

Molecular geometry refers to the three-dimensional arrangement of atoms within a molecule. The shape of a molecule is determined by the number of bonding pairs and lone pairs of electrons around the central atom, which can be predicted using VSEPR (Valence Shell Electron Pair Repulsion) theory. Understanding the geometry is crucial for determining the polarity of the molecule.

Polarity

Polarity in molecules arises from the distribution of electrical charge, leading to regions of partial positive and negative charges. A molecule is considered polar if it has a net dipole moment due to an uneven distribution of electrons, often caused by differences in electronegativity between atoms. Nonpolar molecules, on the other hand, have symmetrical charge distributions that cancel out any dipole moments.

Electronegativity

Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond. Differences in electronegativity between bonded atoms can lead to polar covalent bonds, where electrons are shared unequally. In the context of determining molecular polarity, understanding electronegativity helps predict how the electron density is distributed across the molecule.