Draw a Lewis structure for the following molecules: e. BeCl₂ (Note: This molecule does not follow the octet rule.)

Verified step by step guidance

1. Identify the total number of valence electrons in the molecule. Beryllium (Be) has 2 valence electrons, and each chlorine (Cl) has 7 valence electrons. Since there are two chlorine atoms, calculate the total valence electrons: 2 (from Be) + 2 * 7 (from Cl) = 16 valence electrons.
2. Determine the central atom. In BeCl₂, beryllium (Be) is the central atom because it is less electronegative than chlorine (Cl) and can form bonds with multiple atoms.
3. Draw a skeletal structure. Place the beryllium atom in the center and the two chlorine atoms on either side, connecting each chlorine to the beryllium with a single bond.
4. Distribute the remaining valence electrons. After forming two single bonds, 4 electrons are used (2 for each Be-Cl bond), leaving 12 electrons. Distribute these remaining electrons around the chlorine atoms to satisfy their octet.
5. Check the structure. Ensure that each chlorine atom has 8 electrons (including the shared pair in the bond), and note that beryllium does not follow the octet rule and is stable with only 4 electrons in its valence shell.

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 bonds between atoms. Understanding how to draw Lewis structures is essential for visualizing molecular geometry and predicting the behavior of molecules.

Valence Electrons

Valence electrons are the electrons in the outermost shell of an atom that are involved in forming bonds with other atoms. The number of valence electrons determines how an atom can bond and interact with others. For example, in beryllium chloride (BeCl₂), beryllium has two valence electrons, which it shares with two chlorine atoms, leading to a unique bonding situation.

Octet Rule

The octet rule is a chemical rule of thumb that states atoms tend to bond in such a way that they each have eight electrons in their valence shell, achieving a stable electron configuration. However, some molecules, like BeCl₂, do not follow this rule, as beryllium can be stable with only four electrons around it. Understanding exceptions to the octet rule is crucial for accurately representing certain molecular structures.