Chlorodifluromethane (CHCl2) Lewis Structure and Steps of Drawing
In Chlorodifluromethane (CCl2F2) molecule, there are only one carbon atom, one hydrogen atom, one chlorine atoms and two fluorine atoms. In Chlorodifluromethane lewis structure, there are two C-F single bonds, one C-Cl bond and one C-H bond around the center atom (carbon) in CHClF2 lewis structure. There are no charges on any atom in Dichlorodifluoromethane lewis structure. Carbon atom is the center atom in CHClF2 molecule.
CHClF2 lewis structure
According to the above lewis structure of CHClF2, you can see how chlorine, hydrogen and fluorine atoms are connected with the center atom, carbon. There are only single bonds between chlorine, hydrogen and fluorine atoms with carbon atom. As well, there are no charges on atoms and CHClF2 molecule does not have an overall charge too. 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.
Chlorodifluromethane (CHClF2)
Chlorodifluromethane (CCl2F2) was used as a refrigerant in air refrigeration purposes. But, its usage is reduced drastically due to its property of depletion of ozone layer. It is a clear light colored and non-toxic liquid.
Steps of drawing lewis structure of CHClF2
There are several steps to complete the lewis structure of CHClF2. Each step of drawing is explained in detail in this tutorial.
- Find total number of electrons of the valance shells of carbon, hydrogen 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 CHClF2
There are three elements in CHClF2 molecule; carbon, hydrogen, fluorine and chlorine.
- Carbon is a group IVA element has four electrons in its last valence shell.
- Hydrogen is a group IA element and only has one electron in its last 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 hydrogen atom = 1 * 1 = 4
- valence electrons given by chlorine atoms = 7 * 1 = 7
- valence electrons given by fluorine atom = 7 * 2 = 14
- Total valence electrons = 4 + 1 + 7 + 14 = 26
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, CHClF2, total pairs of electrons are 13 (26/2) in their valence shells.
Center atom selection and draw basic skeletal of CHClF2
To be the center atom, ability of having greater valance and being most electropositive element in the molecule are important facts.
Because, CHClF2 contains several elements, it is bit challenging to select the center atom.
Hydrogen atom cannot be a center atom because hydrogen can only make one covalent bond.
- Considering greater valence - Chlorine's highest valence is 7 and carbons's highest valence is 4. Fluorine's and hydrogen's highest valence is 1. From this case, we can suggest that chlorine has the higher potential to be the center atom.
- Most electropositive element - Carbon's electronegativity is 2.5 and chlorine's electronegativity is 3.16 according to the Pauling's electronegativity scale. Fluorine's and hydrogen's electronegativity values are is 3.98 and 2.2 . Therefore, carbon is more electropositive (excluding hydrogen) than other three atoms. In that case, we can suggest that carbon has the higher 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 chlorine and fluorine atoms
After deciding the center atom and drawing of skeletal structure of CHClF2 molecule, we can start to mark lone pairs on atoms. Remember that, there are total of 13 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 9 (13-4) electron pairs are remaining to mark on atoms.
- Usually, those remaining electron pairs should be started to mark on outside atoms (in this case in chlorine, bromine and hydrogen, but remember that hydrogen cannot keep more lone pairs because hydrogen has already made a single bond with carbon atom).
- Therefore, mark those electrons pairs on chlorine and fluorine atoms ; One chlorine atom will 3 lone pairs. So 3 lone pairs are marked on one chlorine atom. Now there are 6 more lone pairs to mark and and mark them on two fluorine atoms.
- 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 CHClF2.
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