Beryllium chloride (BeCl₂) Lewis structure
16 valence electrons, linear
Build BeCl₂ step by step in the Lewis Structure Generator
What is the Lewis structure of BeCl₂?
Beryllium chloride, BeCl₂, has 16 valence electrons. Beryllium is the central atom, joined by two Be−Cl single bonds. It carries three lone pairs on each Cl. Every formal charge is zero. Be is AX₂: linear, with an ideal bond angle of 180°, and the molecule is nonpolar.
Valence electrons in BeCl₂
In one line: 2 + 2 × 7 = 16. Each atom brings the valence electrons its group gives it.
How to draw the BeCl₂ Lewis structure
- Count the valence electrons. Valence electrons: Be 2 and each Cl 7. 2 + 2 × 7 = 16.
- Choose the central atom. Be goes in the middle: Be is the least electronegative atom other than H, χ 1.57 against 3.16 for Cl.
- Join the atoms with single bonds. Two single bonds use 4 electrons, leaving 16 − 4 = 12.
- Complete the outer atoms. Each outer atom takes enough lone pairs to reach eight: 2 Cl × 6 = 12, leaving 12 − 12 = 0.
- Put the rest on the central atom. Nothing is left, so Be gets no lone pair, and Be now has 4 electrons round it.
- Make multiple bonds where needed. Be is left with 4 electrons. A double bond from an outer atom would complete its octet only by putting positive charge on the more electronegative atom, so Be stays short, one of the known exceptions to the octet rule.
Lone pairs and formal charges in BeCl₂
| Atom | Number | Bonds | Lone pairs | Electrons round it | Formal charge, V − N − B/2 |
|---|---|---|---|---|---|
| Be (central) | 1 | two single bonds | 0 | 4 | 2 − 0 − 2 = 0 |
| Cl | 2 | one single bond | 3 | 8 | 7 − 6 − 1 = 0 |
V is the atom’s valence electrons, N its nonbonding electrons and B its bonding electrons. The formal charges add up to 0, the molecule’s overall charge.
Shape and polarity of BeCl₂
| Central atom | Be |
|---|---|
| VSEPR class | AX₂ |
| Electron geometry | linear |
| Molecular geometry | linear |
| Ideal bond angle | 180° |
| Polarity, an estimate | nonpolar |
In a linear shape identical bonds cancel exactly.
Be has two σ bonds and no lone pairs, two electron domains in all, so its electron geometry is linear. With no lone pairs, the molecular geometry is the same.
The VSEPR Molecular Geometry viewer turns the AX₂ shape in 3D, lone pairs included.
Notes on the BeCl₂ Lewis structure
- Gaseous BeCl₂ is linear with four electrons on beryllium. The solid is a chain in which each beryllium bonds to four chlorines.
Work with BeCl₂
- Lewis Structure Generator: BeCl₂ built step by step, with every formal charge worked out
- VSEPR Molecular Geometry: every VSEPR shape in 3D, with its bond angles
- All 78 Lewis structures: valence electrons, resonance, shape and polarity in one table