Ortho-Dichlorobenzene, C₆H₄Cl₂, is obtained when two of the adjacent hydrogen atoms in benzene are replaced with Cl atoms. A skeleton of the molecule is shown here. (a) Complete a Lewis structure for the molecule using bonds and electron pairs as needed.

Verified step by step guidance

1. Identify the basic structure of benzene, which is a hexagonal ring consisting of six carbon atoms with alternating double bonds and each carbon atom bonded to one hydrogen atom.
2. Replace two adjacent hydrogen atoms in the benzene ring with chlorine (Cl) atoms. This modification will occur at the ortho positions, which are the positions next to each other on the benzene ring.
3. Draw single bonds from the carbon atoms to the chlorine atoms, as chlorine typically forms single bonds in organic compounds.
4. Complete the remaining bonds in the benzene ring. Ensure that each carbon atom forms three bonds in total and maintains the alternating double bond structure where possible. Adjust the double bonds if necessary to accommodate the electron pairs shared with the chlorine atoms.
5. Add lone pairs to the chlorine atoms. Each chlorine atom should have three pairs of lone electrons, which are not involved in bonding but influence the shape and reactivity of the molecule.

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 use dots to represent valence electrons and lines to represent covalent bonds. Understanding how to draw Lewis structures is essential for visualizing molecular geometry and predicting reactivity.

Covalent Bonding

Covalent bonding occurs when two atoms share one or more pairs of electrons, allowing them to achieve a full outer electron shell. In ortho-dichlorobenzene, the carbon atoms in the benzene ring form covalent bonds with chlorine atoms, replacing hydrogen atoms. This concept is fundamental for understanding molecular structure and stability.

Molecular Geometry

Molecular geometry refers to the three-dimensional arrangement of atoms within a molecule. The geometry is influenced by the number of bonds and lone pairs around the central atoms, which can affect the molecule's physical and chemical properties. In ortho-dichlorobenzene, the arrangement of chlorine and carbon atoms will determine the molecule's shape and reactivity.