Becl2 Lewis Structure,Characteristics:13 Must To Know Facts


We’ll talk about  BeCl2 lewis structure, formal charges, geometry, hybridization and their respective uses in this article.

Becl2 or Beryllium Chloride is an inorganic compound which is hygroscopic in nature and soluble in only polar solvents. It can be either white color solid or colorless in nature. The properties of BeCl2 is quite similar to aluminum chloride due to diagonal relationship.

How to draw Becl2 lewis structure?

Before jumping directly to the lewis structure, one should aware of the following terms like valence electrons and the octet rule.

Becl2 valence electrons

The term valence electron count refers to the actual number of electrons that participate in the bond formation. Generally, electrons that are present far from the nucleus are considered as valence electrons as they are readily available in the outermost shells of their respective atoms.

Be stands for Beryllium, an element of the periodic table with atomic number 4 and  with electronic configuration  of [He] 2s² whereas Cl ( chlorine) is part of halogen family with electronic arrangement of [Ne] 3s²3p⁵.

Hence, Be has 2 valence electrons and Cl has 7

Becl2 lewis structure octet rule

 A lewis structure is valid only when the intended entity passes the octet rule. According to the octet rule after the bond formation every atom should have stable electronic configuration.

Let’s draw lewis dots for BeCl2 by following the above mentioned rules:

  • Count the number of electrons that are available for bond formation ( ie. Valence electron)
  •  Select the position of central atom on the basis of electronegativity factor as per rule “ most electropositive atom will occupy the center and atom with electronegative character will occupy the outer positions”
  • Now, assign the all available electrons pairs in such a way that each of participating atoms must left with a stable configuration.

By following the above rules, we get the pictorial representation of Becl2 lewis structure:

Becl2 lewis structure lone pairs

Lone pairs are those non-bonding electrons which  stay as spectators during the process  chemical reaction and do not contribute towards bond formation. Generally, in lewis dots, they represented by dots towards the outer side.

 As, it is clear from the Becl2 lewis structure, Be do not have any lone pairs associated with it whereas chlorine has 6 lone pairs

Becl2 lewis structure resonance

Generally, resonance refers to the exchange of electrons from one bond to another. Conversely, resonance structure only possible only if the involved atoms either unsaturated or have empty d orbitals.

Can resonating structure possible for Becl2?

No, this is because Be does not any d orbitals in its valence shells and hence, resonating structure can not be possible for Becl2.

Becl2 lewis structure formal charge

Formal charge refers to the overall charge carried by a compound.

Formal charge for any compound can be found by using the above formula.

Calculation of formal charge for Berlyium atom

Valence electrons = 2 ( as belong to second group)

Unbonded electron count = 0

Bonded electrons = 4

F.C =  2 – 0 –  4/2 =  0

Calculation of formal charge for chlorine atom

Total valence count = 7

Unbonded electron count = 6

Bonded electrons = 2

F.C = 7 -6 – 2/2 =  0

Hence total formal charge on BeCl2 = 0

Becl2 hybridization

Hybridisation is a process in which two or more atomic orbitals of comparable energies overlap with each other to form hybrid orbitals.

Let’s see how hybridization happens in BeCl2 step by step:

  1. Ground state of Be ( Z=4) [He] 2s²
  2. Ground state of Cl ( z= 17) [Ne] 3s²3p⁵
Ground state of Be and Cl
  • Excited sate of Be and Cl
Representation of excited states of Be and Cl
  • Formation of compound BeCl2

As it is clear from the given figure that formation of BeCl2 involve S and P orbitals and hence hybridisation is SP.

Becl2 lewis structure shape

As per  VSEPR theory, the expected molecular geometry of BeCl2 is found to be linear in shape.

This is because the central atom ie Be has no lone pairs around it and hence left no space for lone pair- lone pair repulsions and also two chlorine atoms attached to the Be also present far from each other in the  two different directions.

 All the arrangement of the atoms in that BeCl2 makes it a linear molecule.

Read more about Gold Structure and Characteristics

Becl2 lewis structure angle

Since the BeCl2 attains Sp hybridization.  The bond angle is expected to 180ºwith  beryllium as central atom containing no  lone pair with it.

Hence, there is no chance for any no disorientation at the  central atom which makes it’s  a perfect linear  shape with a bond angle of 180º. The general structure for linear geometry is given below:

General representation of linear geometry ( wikipedia)

Frequently asked questions

Is Becl2 ionic?

A compound is called ionic only if ionic bonds are established during the formation of the intended compound. However, in the case of BeCl2, the ionic bond cannot be formed because Berliyum has ionization energy around 900 kJ/mol which is relatively higher than the chlorine.

Therefore, the compound BeCl2 is not ionic but covalent in nature.

 What is the solubility of Becl2?

Due to the ionic nature of BeCl2, it is soluble in all polar solvents las given below:

water

acetone

DMSO.

However, it is insoluble in a non-polar solvent like CCl4.

Is Becl2 polar or nonpolar?

The BeCl2 molecule has a linear shape and also both Chlorine atoms attached to the BeCl2 also are in chemically same environment ie has same electronegative. As a result,  the dipole  moment of the BeCl2  molecule becomes zero leaving behind no partial charge.

Is Becl2 acidic or basic?

In order to know the acidic and basic character of BeCl2, Let’s examine the reaction of BeCl2 with water molecule.

BeCl2 + H2O → Be(OH)2 + 2 HCl

As you can observe here, when BeCl2 dissolved in water it produces a strong acid and hence it shows BeCl2 is acidic in nature.

Give physical characteristics of the compound BeCl2.

It gives yellow appearance

Boiling point = 482 °C

Melting point = 399 °C

Density = 1.899 g/cm3

State of matter is solid at room temperature

What are the uses of BeCl2?

1.During synthesis of many beryllium compounds BeCl2 formed as reaction intermediates.

 2. For electrolytic extraction of beryllium BeCl2 is used as  a raw material.

Is BeCl2 toxic in nature?

Direct contact with human skin cause irritation and leads to some allergic reactions. Moreover, longer exposure to this compound can cause lung cancer.

How BeCl2 is prepared?

BeCl2 can be prepared by reacting Berliyum metal with chorine at high temperature as shown above:

Be + Cl2 → BeCl2

What kind of structure BeCl2 have in solid and liquid state?

 BeCl2 have a polymeric chain structure in the solid state in which Be atom has four chlorine atoms in its surrounding. Out of 4, two chlorine atoms attached to the central atom via covalent bond and rest two with the coordinate bond as shown in the above figures

Structure of BeCl2     in the  solid state

 In the case of liquid state, polymeric structure of Becl2 is dissociates into monomers and exist as BeCl2 in linear shape.

    BeCl2​ in the  liquid state

Conclusion

To conclude, Becl2 has sp hybridization with a linear geometry , followed the octet rule and reported with zero formal charges.

Pomila Sharma

Hello...Myself is Pomila Sharma. I have done my master's in Chemistry with a specialization in synthetic organic chemistry. I have published 4 research articles. I am very passionate about the chemistry world. I believe it's all about chemistry so let’s explore it together. LinkedIn link: https://www.linkedin.com/in/pomila008

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