BeCl2 Lewis Structure
Beryllium chloride · A linear molecule in the gas phase; in the solid it links up into chains.
The BeCl2 Lewis structure has 16 valence electrons, drawn as two Be–Cl bonds, with six lone pairs in total. The central Be is sp hybridized and the molecule is linear, with a bond angle of 180 degrees. BeCl2 is nonpolar: the bond dipoles are all the same size and the shape places them symmetrically around the central Be, so they cancel exactly.
- 16 valence e−
- linear
- 180° bond angle
- sp
- nonpolar
At least one atom does not reach a full octet in this structure.
BeCl2 molecular geometry
Linear, from 2 electron domains on the central Be: 2 bonded atoms (AX2). The electron geometry is linear. Wedges point toward you, hashed wedges away. Every shape in the VSEPR chart →
Calculated properties
| Total valence electrons | 16 |
|---|---|
| Bonding electrons | 4 (2 shared pairs) |
| Nonbonding electrons | 12 (6 lone pairs) |
| Lone pairs on Be | 0 |
| Electron domains (steric number) | 2 |
| VSEPR notation | AX2 |
| Electron geometry | linear |
| Molecular geometry | linear |
| Bond angle | 180° |
| Hybridization | sp |
| Polarity | nonpolar |
| Formal charges | all zero |
| Resonance structures | none |
| Molar mass | 79.912 g/mol |
Be Beryllium 2 valence e− Cl Chlorine 2 atoms, 7 valence e− each
How to draw the BeCl2 Lewis structure
Step through it. The bar shows how much of the 16-electron budget is spent at each stage - it never grows, which is the whole constraint.
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Skeleton. Join every connected pair with one bond. 2 bonds spends 4 electrons.
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Outer octets. Spend electrons as lone pairs on the outer atoms. That uses the entire budget, and the central atom has nothing left over.
The reasoning at each step
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Count the valence electrons
Add up the outer-shell electrons every atom brings. That total is the budget for the whole structure - every line and every dot has to come out of it, and nothing may be added.
2 (Be) + 2 x 7 (Cl) = 16 valence electrons -
Choose the central atom
Be is the least electronegative atom here, so it takes the centre. Hydrogen is never central: it can only form one bond.
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Join everything with single bonds first
Every connection starts as one shared pair. Draw them all before worrying about double bonds - the arithmetic in the next step is what tells you where the double bonds have to go.
2 bonds x 2 = 4 electrons used, 12 left -
Work out how far short you are
Add up what every atom still needs to fill its shell - eight electrons for most atoms, two for hydrogen - minus what its single bonds already give it. Compare that with the electrons you have left. The difference decides everything that follows.
needs 16, has 12, short by 4 -
Accept an incomplete octet
You are 4 electrons short, and the only way to close the gap would be a double bond to a halogen - which is not something these atoms do. Be stays below eight electrons instead. That is real chemistry, not a mistake.
Be: 4 electrons -
Fill in the lone pairs
Every electron not in a bond sits as a lone pair on an atom. Each atom takes exactly what it needs to finish its shell - there is no choice left at this point.
Cl1: 3, Cl2: 3 (12 electrons) -
Check the central atom
Be ends up with 4 electrons, short of an octet, which is correct for this molecule.
Be: 4 bonding + 0 nonbonding = 4 -
Check the formal charges
Formal charge is valence electrons, minus lone-pair electrons, minus the number of bonds. Every atom here comes out at zero, which is the sign of a good structure.
all formal charges = 0 -
Work out the shape
Count the electron domains on Be: 2 bonded groups. A double or triple bond still counts as one domain, because it points in one direction. That gives linear electron geometry; ignore the lone pairs and the atoms themselves sit in a linear arrangement.
steric number 2 -> sp -> linear, bond angle 180 -
Decide whether it is polar
The bond dipoles are all the same size and the shape places them symmetrically around the central Be, so they cancel exactly.
dipoles cancel -> nonpolar
Is BeCl2 polar or nonpolar?
BeCl2 is nonpolar. The bond dipoles are all the same size and the shape places them symmetrically around the central Be, so they cancel exactly.
| Bond | Electronegativity difference | Character |
|---|---|---|
| Be–Cl | 1.59 | polar covalent |
Common questions
How many valence electrons does BeCl2 have?
BeCl2 has 16 valence electrons. 4 of them are in bonds and 12 sit in lone pairs.
What is the molecular geometry of BeCl2?
BeCl2 is a linear molecule. The central Be has 2 bonded groups, a steric number of 2, which gives linear electron geometry and a linear molecule.
What is the bond angle in BeCl2?
The bond angle in BeCl2 is 180 degrees. That is the ideal linear angle, and nothing distorts it here.
What is the hybridization of BeCl2?
The central Be in BeCl2 is sp hybridized. Steric number 2 means 2 orbitals have to be mixed, which is exactly what sp gives you.
Is BeCl2 polar or nonpolar?
BeCl2 is nonpolar. The bond dipoles are all the same size and the shape places them symmetrically around the central Be, so they cancel exactly.