Trichloromonofluoromethane (CCl3F) Lewis Structure and Steps of Drawing
In Trichloromonofluoromethane molecule,
there are one carbon atom, three chlorine atoms and one fluorine atom.
In Trichloromonofluoromethane lewis structure, there are three C-Cl single bonds and one C-F bond around carbon atom in CCl3F lewis structure. There are no charges
on any atom in Trichloromonofluoromethane lewis structure. Carbon atom is the center atom in CCl3F molecule.
CCl3F lewis structure
According to the lewis structure of CCl3F, you can see how chlorine and fluorine atoms are connected with the center atom,
carbon. There are
only single bonds between chlorine and
fluorine atoms with carbon atom. As well, there are no charges on atoms and
CCl3F molecule does not have an overall charge. Each chlorine and fluorine atom has three lone pairs in their valence shells
and carbon atom does not have lone pairs in it's valence shell.
There are several steps to complete the lewis structure of CCl3F. Each step of drawing is explained in detail in this tutorial.
Find total number of electrons of the valance shells of carbon, chlorine and fluorine atoms
Determine total electrons pairs as lone pairs and bonds
Find center atom and draw basic skeletal structure
Mark lone pairs on atoms
Mark charges on atoms if there are charges.
Check the stability and minimize charges on atoms by converting lone pairs to bonds to obtain best
lewis structure.
Total number of electrons of the valance shells of CCl3F
There are three elements in CCl3F molecule; carbon, fluorine and chlorine.
Carbon is a group IVA element has four electrons in its last valence shell.
Chlorine is a group VIIA element in the periodic table and contains 7 electrons in its last shell.
Fluorine is also a group VIIA element in the periodic table and contains 7 electrons in its last shell.
Now we know how many electrons are included in valence shells of each atom.
valence electrons given by carbon atom = 4 * 1 = 4
valence electrons given by chlorine atoms = 7 * 3 = 21
valence electrons given by fluorine atom = 7 * 1 = 7
Total valence electrons = 4 + 21 + 7 = 32
Total valence electrons pairs
Total valance electrons
pairs = σ bonds + π bonds + lone pairs at valence shells
Total electron pairs are determined by dividing the number total valence electrons by two. For,
CCl3F, total pairs of electrons are 16 (32/2) in their valence shells.
Center atom selection and draw basic skeletal of CCl3F
To be the center atom, ability of having greater valance and being most electropositive element in the
molecule are important facts.
Because, CCl3F is a simple molecule, it is not very difficult to select the center atom.
Considering greater valence - Chlorine's highest valence is 7 and carbons's highest valence is 4.
Fluorine's highest valence is 1. From this case, we can suggest that chlorine has the potential to be the center atom.
Most electropositive element - Carbon's electronegativity is 1.9 and chlorine's electronegativity is 3.16
according to the Pauling's electronegativity scale. Fluorine's electronegativity is 3.98. Therefore, carbon is more
electropositive than other two atoms. In that case, we can suggest that carbon has the potential to be the center atom.
Now, there is a confusion between how to select the center atom between carbon and chlorine.
Now, we are going to consider the minimum valence of chlorine and carbon atoms to form stable compounds.
Chlorine's minimum valence is 1 and carbon's minimum (only) valence is 4. That means, there should be minimum
number of four bonds around carbon atom, if carbon form a stable compound.
From above finding, we understand that carbon atom should be the center atom and basic skeletal structure can be
drawn as below.
Mark lone pairs on atoms
After deciding the center atom and drawing of skeletal structure of CCl3F molecule, we can start to mark lone pairs on atoms.
Remember that, there are total of 16 electron pairs to mark on atoms as bonds and lone pairs.
There are already 4 single bonds in the above drawn skeletal structure. Now only 12 (16-4) electron pairs
are remaining to mark on atoms.
Usually, those remaining electron pairs should be started to mark on outside atoms.
Therefore, mark those electrons pairs on each chlorine atom; One chlorine atom will 3 lone pairs. So 9 lone pairs
are marked on all three chlorine atoms. Now there are 3 more lone pairs and mark them on fluorine atom.
Now, all lone pairs are marked on atoms.
Mark charges on atoms if there are and check the stability and minimize charges on atoms by converting lone pairs to bonds
There are no charges on any atom and we do not need to the step of reducing charges of atoms. It means that, we
have obtained the lewis structure of CCl3F.