- Draw The Most Appropriate Lewis Structure(S) For BeF2. What Is The Electron Domain Geometry And The Molecular Geometry? Does The Molecule Have A Dipole? What Is The Hybridization Of The Central Atom? How Many O And It Bonds Are There?
The Correct Answer and Explanation is :
Lewis Structure for BeF2
To draw the Lewis structure for beryllium fluoride (BeF₂), follow these steps:
- Determine the total number of valence electrons:
- Beryllium (Be) has 2 valence electrons (group 2 element).
- Fluorine (F) has 7 valence electrons, and there are two fluorine atoms.
- Total electrons = 2 (from Be) + 7 × 2 (from F) = 16 electrons.
- Place the central atom (Be) and surrounding atoms (F):
- Place Be in the center because it is less electronegative than F.
- Connect each F to Be with a single bond, which uses 4 electrons (2 electrons per bond).
- The remaining 12 electrons will be placed as lone pairs on the fluorine atoms.
- Distribute the electrons:
- After bonding, 12 electrons remain. Assign these electrons as lone pairs to the fluorine atoms.
- Each fluorine will get three lone pairs, leaving each fluorine atom with a complete octet.
Thus, the Lewis structure for BeF₂ is:
F-Be-F
With each F atom having 3 lone pairs.
Electron Domain Geometry and Molecular Geometry
- Electron Domain Geometry: Be has two bonds and no lone pairs around it, which gives an electron domain geometry of linear.
- Molecular Geometry: Since there are no lone pairs on the central atom (Be), the molecular geometry is also linear.
Dipole Moment
- Dipole Moment: The molecule does not have a dipole moment because BeF₂ is symmetric, with two fluorine atoms on opposite sides of the beryllium atom. The dipoles created by each Be-F bond cancel each other out, leading to no overall dipole moment.
Hybridization of the Central Atom
- Hybridization: The central atom Be has two bonding regions (two Be-F bonds). Therefore, the hybridization is sp.
O and I Bonds
- In BeF₂, the molecule consists of 2 single bonds between the beryllium and fluorine atoms (I-type bonds). There are no O bonds in this structure.
Summary
- Lewis Structure: Be-F-Be with lone pairs on fluorine.
- Electron Domain Geometry: Linear.
- Molecular Geometry: Linear.
- Dipole Moment: No dipole moment.
- Hybridization: sp.
- Bonds: 2 I-type (Be-F) bonds, no O bonds.