SHORT ANSWER Draw a Lewis electron-dot structure for LiBr. Include any charges or partial charges. Draw a Lewis electron-dot structure for CaCl2. Include any charges or partial charges. Explain, in terms of valence electrons, why the bonding LiBr is similar to the bonding in CaCl2. 2. Draw the Lewis Dot structure of HBr. Include any charges or partial charges if necessary. Draw the Lewis Dot structure of MgCl2. Include any charges or partial charges if necessary.
The Correct Answer and Explanation is:
Lewis Dot Structure of LiBr:
- Lithium (Li) has 1 valence electron, which it donates to form a +1 cation (Li⁺).
- Bromine (Br) has 7 valence electrons and gains the electron from lithium to form a -1 anion (Br⁻).
The Lewis structure for LiBr is:
- Li⁺ [Br]⁻ (The lithium ion is represented with no dots, and the bromine ion has 8 dots around it, representing a full valence shell).
Lewis Dot Structure of CaCl2:
- Calcium (Ca) has 2 valence electrons and donates both to form a +2 cation (Ca²⁺).
- Chlorine (Cl) has 7 valence electrons and each chlorine atom gains one electron to form a -1 anion (Cl⁻).
The Lewis structure for CaCl₂ is:
- Ca²⁺ [Cl]⁻ [Cl]⁻ (The calcium ion is represented with no dots, and each chlorine ion has 8 dots around it).
Explanation:
Both LiBr and CaCl₂ are ionic compounds formed by the transfer of electrons. In LiBr, lithium donates its single valence electron to bromine, while in CaCl₂, calcium donates two valence electrons, one to each chlorine. This results in the formation of oppositely charged ions, which are held together by electrostatic attraction. The ionic nature of these bonds is due to the differences in electronegativity between the metal and nonmetal. In both compounds, the metals (Li and Ca) become positively charged cations, while the nonmetals (Br and Cl) become negatively charged anions. This is similar in both compounds, as both involve the transfer of electrons from metals to nonmetals to achieve full valence shells.
Lewis Dot Structure of HBr:
- Hydrogen (H) has 1 valence electron, and Bromine (Br) has 7 valence electrons.
- Hydrogen shares its electron with bromine, forming a single covalent bond.
The Lewis structure for HBr is:
- H—Br (A single line represents the shared pair of electrons between hydrogen and bromine).
Lewis Dot Structure of MgCl2:
- Magnesium (Mg) has 2 valence electrons and donates both to form a +2 cation (Mg²⁺).
- Chlorine (Cl) has 7 valence electrons and each chlorine atom gains one electron to form a -1 anion (Cl⁻).
The Lewis structure for MgCl₂ is:
- Mg²⁺ [Cl]⁻ [Cl]⁻ (The magnesium ion has no dots, and each chlorine ion has 8 dots around it).
These Lewis structures illustrate how both ionic and covalent bonding result from the interaction of atoms trying to achieve stable electron configurations.
