Cfcl3 lewis structure,Characteristics:13 Must To Know Facts

This article is about CFCl3 which is a greenhouse gas and is responsible for ozone depletion. Let’s have a look at some of its interesting characteristics –

The CFCl3 Lewis structure consists of one central atom carbon, 3 chlorine atoms and a fluorine atom are present around the carbon atom. The Lewis structure of CFCl3 molecule has 12 lone pairs.

                     

Molecular NameTrichlorofluoromethane
Also known as CFC-11                          
  Freon-11                              
R-11Chemical FormulaCFCl3Central atom of the lewis structureCarbonlone pairs present on the central atom 0Molecular Geometry of CFCl3Tetrahedral  Electron Geometry of CFCl3TetrahedralBond angle in CFCl3109.5No. of valence electron for CFCl3
32
The formal charge of CFCl3 molecule0
Nature of the compoundCFCl3 is an inert compound
Characteristics of CFCl3

How should we draw the Lewis dot structure for CFCl3?

The steps to be followed while drawing the Lewis structure of CfCl3 molecule are as follows –

 Step 1: Find the total valence electrons in the CFCl3 molecule

First step is to find the no. of valence electrons present in CFCl3 molecule.

Carbon is a member of group 14th while Fluorine and Chlorine are the members of group 17th of the periodic table.

Carbon has valence electrons = 4

Chlorine has valence electrons = 7

Fluorine has valence electrons = 7

 Valence electronsAtom In CBr4Total Electrons
C             4        1 4*1= 4
F             7        1 7*1= 7
Cl             7        3 7*3= 21     
              32
Valence electrons for CFCl3

Step 2: Get the least electronegative element present in CFCl3

In a period, as we move from left to right Electronegativity increases so carbon is least electronegative than chlorine and fluorine. We have to keep the least electronegative atom in the centre.

The skeletal structure of CFCl3 molecule is as follows –

image 51
A picture containing drawing  Description automatically generatedstep2:
Skeletal Structure of CFCL3

Step 3: Keep two electrons or a bond between C, F and Cl atoms

                                    

image 52
A picture containing drawing  Description automatically generatedStep 3: Drawing Lewis structure of CFCl3

Step 4: Now find the number of electrons which can make the outer atoms happy

The outer atoms will be happy when they have achieved the octet configuration of their nearest noble gas element belonging to group 18th.This is what we call the Octet Rule. Except hydrogen which tries to attain the duplet configuration like He.

Complete the octet of the surrounding atoms

                                                    

image 53
A picture containing drawing  Description automatically generatedstep 4: Drawing Lewis structure Of CFCl3

                                    

Step 5: Place the remaining electrons on the central atom. If the octet of the central atom is not achieved, we can move the lone pairs from the outer atoms to make multiple bonds if required

This step is not required for CFCl3 as the central atom’s octet is already

Completed.

                                 

Step 6: We can now check the stability of the Lewis structure by checking the formal charge values

Before accepting the structure as a perfect Lewis structure, we will check the formal charge for the atoms present in CFCl3

Formal charge = Valence electrons – 1/2*bonding electrons – non-          bonding electrons

The formal charge for Carbon is –

The valence electrons of Carbon are 4

The non-bonding electrons of carbon are 0

The bonding electrons of carbon are 8 (4 pairs)

The formal charge for carbon atom = 4 – 1/2*8 – 0 = 0

The formal charge for Fluorine is –

The valence electrons of Fluorine are 7

The non-bonding electrons of Fluorine are 6 (3 lone pairs)

The bonding electrons for Fluorine are 2

The formal charge for Fluorine atom = 7 – 1/2*2 – 6 = 0

The Formal charge for Chlorine is – 

The valence electrons of Chlorine are 7

The non-bonding electrons of Fluorine is 6 (3 lone pairs)

The bonding electrons for Fluorine are 2

The formal charge for Fluorine atom = 7 – 1/2*2 – 6 = 0

As the C, F and Cl elements have least possible formal charge, we have obtained suitable Lewis structure

What is the formal charge of CFCl3 and how to calculate the formal charge values for CFCl3?

 Let’s calculate the formal charge for CFCl3 –

Formal charge = Valence electrons – 1/2*bonding electrons – non-bonding electrons

The formal charge for Carbon is –

The valence electrons of Carbon are 4

The non-bonding electrons of Carbon are 0

The bonding electrons for Carbon are 8 (4 pairs)

The formal charge for Carbon atom = 4 – (1/2) * 8 – 0 = 0

The formal charge for Fluorine –

The valence electrons of Fluorine are 7

The non-bonding electrons of Fluorine are 6 (3 lone pairs)

The bonding electrons for Fluorine are 2

The formal charge for Fluorine atom =7 – (1/2) * 2 – 6 = 0

The formal charge for chlorine is –

The valence electrons of Chlorine are 7

The non-bonding electrons of Chlorine are 6 (3 lone pairs)

The bonding electrons of Chlorine are 2

The formal charge for Chlorine atom = 7 – (1/2) * 2 – 6 = 0

The formal charge on carbon, fluorine and chlorine atom in CFCl3 Lewis dot structure is zero.

How can we know whether CFCl3 molecule follows the octet rule?

CFCl3 contains 32 valence electrons. Each and every atom of CFCl3 complete its octet that can be confirmed from the Lewis structure of CFCl3 molecule. This confirms that CFCl3 molecule follows the octet rule.

How to find the molecular shape and electron geometry of CFCl3 molecule?

We can find the molecular and electron geometry of CFCl3 molecule in  three simple steps  –

1) Calculate the non-bonding electron pairs on the central atom carbon

 Lone Pair = (1/2) * (V.E. –N.A.)

Here –

V.E. stands for the valence electrons on the central atom

N.A stands for the number of atoms which are bonded to the central atom

The central atom carbon in CFCl3 molecule has 4 valence electrons and 4 atoms are attached to it.

Lone Pairs = (1/2) * (4 – 4) = 0

2) Find out the hybridization number of the central atom

We can know the hybridization of central atom with the help of the formula –

Hybridization number = N.A. + L.P

Where-

N.A. stands for the number of atoms attached to the central atom

L.P.  stands for the number of lone pairs on the central atom

The central carbon atom has 4 atoms bonded to it and there are no lone pairs on it.

 The central atom in CFCl3 molecule is Sp3 hybridized.

3) Determine molecular/electron geometry of CFCl3 molecule by using VSEPR Theory

We have already found out the hybridization of CFCl3 as Sp3 and there are no lone pairs present on the central atom.

Now find the VSEPR notation for CFCl3 molecule according to AXnEx notation of VSEPR theory

In AXnEx notation  –

 A stand for the central atom

 X stands for the number of atoms attached to the central atom

  E stands for the number of lone pairs of electrons on the central atom

In accordance with to the Trichlorofluoromethane Lewis structure, carbon is the central atom to which 1 fluorine atom and 3 chlorine atoms are attached.

The central atom carbon has no lone pairs present on it so the formula of CFCl3 comes out to be AX4

Using the VSEPR chart, molecule having AX4 formula has tetrahedral molecular shape and electron geometry also tetrahedral.

Total DomainsGeneral FormulaBonded atomsLone PairsMolecular ShapeElectron Geometry
1AX10LinearLinear
2AX220LinearLinear
 AXE11LinearLinear
3AX330Trigonal PlanarTrigonal Planar
 AX2E21BentTrigonal Planar
 AXE212LinearTrigonal Planar
4AX440TetrahedralTetrahedral
 AX3E31Trigonal PyramidTetrahedral
 AX2E222BentTetrahedral
 AXE313LinearTetrahedral
VSEPR CHART

           Thus, the molecular geometry and also the electron geometry of CFCl3 is Tetrahedral.                                 

Is CFCl3 molecule polar or non-polar?

CFCl3 is a polar molecule is confirmed by three factors –

1)Electronegativity:

Chlorine (electronegativity 3.0) and Fluorine (electronegativity 4.0) are more electronegative than carbon (electronegativity2.5). As chlorine and fluorine are more electronegative than carbon, there is a separation of charges between carbon and chlorine/fluorine.

Fluorine is even more electronegative so there is a charge separation between carbon and fluorine but charge separation of C-F is in the opposite direction

to that of the charge separation by C-Cl.

A molecule is said to be polar when the difference in electronegativity between the atoms in the given molecule is more than 0.4 debye.

2)Geometrical/Molecular Shape: 

Geometrical Structure of CFCl3 molecule is tetrahedral.

The four dipoles of three C-Cl bonds and one C-F bond are in opposite directions.

3)Dipole Moment:

CFCl3 has Dipole moment of 0.45D

All these factors show that CFCl3 is a polar molecule.

What is the hybridization for CFCl3 molecule?

The four valence electrons of the central atom carbon atom are shared with 3 chlorine atoms and 1 Fluorine atom. To share the electrons with fluorine and chlorine, the orbitals of carbon atom undergo sp3 hybridization.

The electronic configuration of Carbon in ground state is 1s2 2s2 2p2

The electronic configuration of Chlorine in ground state is 1s2 2s2 2p6 3s2 3p5

The electronic configuration of Fluorine in ground state 1s2 2s2 2p5

The electronic configuration of Carbon after carbon has gain four electrons from three Chlorine atoms and one Fluorine atom is –  1s2 2s2 2px2 2py2 2pz2

Steric Number = Number of atoms attached to the central atom + Number of lone pairs of electrons on the central atom

Steric Number = 4 + 0 = 4

So in CFCl3, the central atom carbon is  Sp3 hybridised.

Is CFCl3 molecule show resonance?                                             

A molecule can only show resonance either when the molecule has either conjugate bonds or it has lone pair in conjugation with the double bond.

Trichlorofluoromethane does not possess double bond so CFCl3 do not show resonance.

Is CFCl3 a covalent compound?

CFCl3 is a covalent compound as the C-F and all the three C-Cl bonds in CFCl3 are formed by sharing of electrons.

What Is the geometry of CFCl3?

The C-F and C-Cl bond lengths in CFCL3 are different so CFCl3 has slightly distorted tetrahedral geometry.

                                                     Tetrahedral geometry of CFCl3

What is the bond angle in CFCl3 molecule?

In the CFCl3 molecule, C-Cl and C-Cl bond pair repulsions are more than the C-F and C-Cl bond pair repulsions

The Cl-C-Cl angles measure slightly more than F-C-F bond angle.

The bond angle in CFCl3 is around 109.5 degrees.

image 54
A picture containing drawing  Description automatically generatedBond angle in CFCl3

Is CFCl3 an acidic or a basic compound?

CFCl3 is neither acidic nor basic in nature. CFCl3 is an inert compound.

But as it comes in contact with the ozone, it undergoes photolysis and gives out chlorine atoms which causes depletion of the ozone layer.

Is CFCl3 soluble in water?

No, CFCl3 not soluble in water. This can be known by the fact it does not get washed out from the atmosphere by precipitation.

Conclusion:

The CFCl3 also known as Freon-11 or CFC-11 is a green house gas.The molecular geometry and also the electron geometry of CFCl3 is tetrahedral. The CFCl3 is insoluble in water. CFCl3 is an inert compound.

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