Write the Lewis structure for IBr; on your paper. Include formal charges on all atoms. Include all resonance structures if there is resonance in this molecule. Answer the following questions for the central atom in the species 1. Select the correct number of electron domains Select) 2. Select the correct number of bonding domains (Select] 3. Select the correct number of nonbonding domains 1 Select) ? 1. How many o bonds are in the molecule Select 2. How many t-bonds are in the molecule Select 3. What atomic orbitals are used by I to make a bonds? Select 4. What atornic orbitals are used by Br to make a bonds? Select 5. Does this molecule have resonance structures and if so, now many? Select 6. Is this a polar or nonpolar species? Select
The Correct Answer and Explanation is :
Explanation and Analysis for IBr
Lewis Structure
- IBr is a diatomic molecule composed of iodine (I) and bromine (Br). Both belong to group 17 (halogens) and have 7 valence electrons each.
- Iodine and bromine form a single covalent bond, and each atom has 3 lone pairs of electrons around it. The Lewis structure is:
:Br—I: - There are no formal charges because each atom achieves the expected octet.
Electron Domains
- Number of Electron Domains:
- The central atom (Iodine) has 4 electron domains: 1 bonding domain and 3 nonbonding domains (lone pairs).
- Number of Bonding Domains:
- Iodine has 1 bonding domain from the single bond with bromine.
- Number of Nonbonding Domains:
- Iodine has 3 nonbonding domains corresponding to the 3 lone pairs of electrons.
Bonding Analysis
- Sigma (σ) Bonds:
- There is 1 sigma bond between iodine and bromine.
- Pi (π) Bonds:
- There are 0 pi bonds since the bond between I and Br is a single bond.
- Atomic Orbitals Used by Iodine:
- Iodine uses an sp³ hybrid orbital for sigma bonding.
- Atomic Orbitals Used by Bromine:
- Bromine also uses an sp³ hybrid orbital for sigma bonding.
Additional Questions
- Resonance Structures:
- No resonance structures exist for IBr, as it is a single bond with lone pairs localized on the atoms.
- Polarity:
- IBr is a polar molecule because bromine is more electronegative than iodine, creating a dipole moment.
Key Takeaways
- Electron domain geometry: Tetrahedral.
- Molecular geometry: Linear (only 2 atoms).
- Polarity arises due to unequal electron distribution.
- The absence of resonance simplifies its electronic structure.